840_C. On the Bench_33207
A year ago on the bench in public park Leha found an array of n numbers. Leha believes that permutation p is right if for all 1 ≤ i < n condition, that api·api + 1 is not perfect square, holds. Leha wants to find number of right permutations modulo 109 + 7.

Input

First line of input data contains single integer n (1 ≤ n ≤ 300) — length of the array.

Next line contains n integers a1, a2, ... , an (1 ≤ ai ≤ 109) — found array.

Output

Output single integer — number of right permutations modulo 109 + 7.

Examples

Input

3
1 2 4


Output

2


Input

7
5 2 4 2 4 1 1


Output

144

Note

For first example:

[1, 2, 4] — right permutation, because 2 and 8 are not perfect squares.

[1, 4, 2] — wrong permutation, because 4 is square of 2.

[2, 1, 4] — wrong permutation, because 4 is square of 2.

[2, 4, 1] — wrong permutation, because 4 is square of 2.

[4, 1, 2] — wrong permutation, because 4 is square of 2.

[4, 2, 1] — right permutation, because 8 and 2 are not perfect squares.
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.util.Arrays;
import java.io.IOException;
import java.io.UncheckedIOException;
import java.io.Closeable;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) throws Exception {
        Thread thread = new Thread(null, new TaskAdapter(), "", 1 << 27);
        thread.start();
        thread.join();
    }

    static class TaskAdapter implements Runnable {
        @Override
        public void run() {
            InputStream inputStream = System.in;
            OutputStream outputStream = System.out;
            FastInput in = new FastInput(inputStream);
            FastOutput out = new FastOutput(outputStream);
            COnTheBench solver = new COnTheBench();
            solver.solve(1, in, out);
            out.close();
        }
    }

    static class COnTheBench {
        Modular mod = new Modular(1e9 + 7);
        Factorial fact = new Factorial(1000, mod);
        Combination comb = new Combination(fact);
        Debug debug = new Debug(true);

        public int f(int i, int j) {
            int ans = mod.mul(fact.fact(i), comb.combination(i + j - 1 - j, j - 1));
            ans = mod.mul(ans, fact.invFact(j));
            return ans;
        }

        public void solve(int testNumber, FastInput in, FastOutput out) {
            int n = in.readInt();
            DSU dsu = new DSU(n);
            long[] a = new long[n];
            for (int i = 0; i < n; i++) {
                a[i] = in.readInt();
            }
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < i; j++) {
                    if (square(a[j] * a[i])) {
                        dsu.merge(j, i);
                        break;
                    }
                }
            }

            IntegerList list = new IntegerList();
            for (int i = 0; i < n; i++) {
                if (dsu.find(i) == i) {
                    list.add(dsu.size[dsu.find(i)]);
                }
            }

            int[] cnts = list.toArray();
            debug.debug("cnts", cnts);
            int m = cnts.length;
            int[][] dp = new int[m + 1][n + 1];
            dp[0][0] = 1;
            for (int i = 1; i <= m; i++) {
                int way = cnts[i - 1];
                for (int j = 0; j <= n; j++) {
                    dp[i][j] = 0;
                    for (int k = 1; k <= j && k <= way; k++) {
                        int contrib = mod.mul(f(way, k), dp[i - 1][j - k]);
                        dp[i][j] = mod.plus(dp[i][j], contrib);
                    }
                }
            }
            debug.debug("dp", dp);

            int ans = 0;
            for (int i = 0; i <= n; i++) {
                int local = mod.mul(dp[m][i], fact.fact(i));
                if ((n - i) % 2 == 1) {
                    local = mod.valueOf(-local);
                }
                ans = mod.plus(ans, local);
            }

            out.println(ans);
        }

        public boolean square(long x) {
            long l = 1;
            long r = (long) 1e9;
            while (l < r) {
                long m = (l + r) / 2;
                if (m * m < x) {
                    l = m + 1;
                } else {
                    r = m;
                }
            }
            return l * l == x;
        }

    }

    static class IntegerList implements Cloneable {
        private int size;
        private int cap;
        private int[] data;
        private static final int[] EMPTY = new int[0];

        public IntegerList(int cap) {
            this.cap = cap;
            if (cap == 0) {
                data = EMPTY;
            } else {
                data = new int[cap];
            }
        }

        public IntegerList(IntegerList list) {
            this.size = list.size;
            this.cap = list.cap;
            this.data = Arrays.copyOf(list.data, size);
        }

        public IntegerList() {
            this(0);
        }

        public void ensureSpace(int req) {
            if (req > cap) {
                while (cap < req) {
                    cap = Math.max(cap + 10, 2 * cap);
                }
                data = Arrays.copyOf(data, cap);
            }
        }

        public void add(int x) {
            ensureSpace(size + 1);
            data[size++] = x;
        }

        public void addAll(int[] x, int offset, int len) {
            ensureSpace(size + len);
            System.arraycopy(x, offset, data, size, len);
            size += len;
        }

        public void addAll(IntegerList list) {
            addAll(list.data, 0, list.size);
        }

        public int[] toArray() {
            return Arrays.copyOf(data, size);
        }

        public String toString() {
            return Arrays.toString(toArray());
        }

        public boolean equals(Object obj) {
            if (!(obj instanceof IntegerList)) {
                return false;
            }
            IntegerList other = (IntegerList) obj;
            return SequenceUtils.equal(data, 0, size - 1, other.data, 0, other.size - 1);
        }

        public int hashCode() {
            int h = 1;
            for (int i = 0; i < size; i++) {
                h = h * 31 + Integer.hashCode(data[i]);
            }
            return h;
        }

        public IntegerList clone() {
            IntegerList ans = new IntegerList();
            ans.addAll(this);
            return ans;
        }

    }

    static class Combination implements IntCombination {
        final Factorial factorial;
        final Modular modular;

        public Combination(Factorial factorial) {
            this.factorial = factorial;
            this.modular = factorial.getModular();
        }

        public Combination(int limit, Modular modular) {
            this(new Factorial(limit, modular));
        }

        public int combination(int m, int n) {
            if (n > m) {
                return 0;
            }
            return modular.mul(modular.mul(factorial.fact(m), factorial.invFact(n)), factorial.invFact(m - n));
        }

    }

    static class FastInput {
        private final InputStream is;
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastInput(InputStream is) {
            this.is = is;
        }

        private int read() {
            while (bufLen == bufOffset) {
                bufOffset = 0;
                try {
                    bufLen = is.read(buf);
                } catch (IOException e) {
                    bufLen = -1;
                }
                if (bufLen == -1) {
                    return -1;
                }
            }
            return buf[bufOffset++];
        }

        public void skipBlank() {
            while (next >= 0 && next <= 32) {
                next = read();
            }
        }

        public int readInt() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            int val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

    }

    static interface IntCombination {
    }

    static class FastOutput implements AutoCloseable, Closeable, Appendable {
        private StringBuilder cache = new StringBuilder(10 << 20);
        private final Writer os;

        public FastOutput append(CharSequence csq) {
            cache.append(csq);
            return this;
        }

        public FastOutput append(CharSequence csq, int start, int end) {
            cache.append(csq, start, end);
            return this;
        }

        public FastOutput(Writer os) {
            this.os = os;
        }

        public FastOutput(OutputStream os) {
            this(new OutputStreamWriter(os));
        }

        public FastOutput append(char c) {
            cache.append(c);
            return this;
        }

        public FastOutput append(int c) {
            cache.append(c);
            return this;
        }

        public FastOutput println(int c) {
            return append(c).println();
        }

        public FastOutput println() {
            cache.append(System.lineSeparator());
            return this;
        }

        public FastOutput flush() {
            try {
                os.append(cache);
                os.flush();
                cache.setLength(0);
            } catch (IOException e) {
                throw new UncheckedIOException(e);
            }
            return this;
        }

        public void close() {
            flush();
            try {
                os.close();
            } catch (IOException e) {
                throw new UncheckedIOException(e);
            }
        }

        public String toString() {
            return cache.toString();
        }

    }

    static class InverseNumber {
        int[] inv;

        public InverseNumber(int[] inv, int limit, Modular modular) {
            this.inv = inv;
            inv[1] = 1;
            int p = modular.getMod();
            for (int i = 2; i <= limit; i++) {
                int k = p / i;
                int r = p % i;
                inv[i] = modular.mul(-k, inv[r]);
            }
        }

        public InverseNumber(int limit, Modular modular) {
            this(new int[limit + 1], limit, modular);
        }

    }

    static class Debug {
        private boolean offline;
        private PrintStream out = System.err;
        static int[] empty = new int[0];

        public Debug(boolean enable) {
            offline = enable && System.getSecurityManager() == null;
        }

        public Debug debug(String name, Object x) {
            return debug(name, x, empty);
        }

        public Debug debug(String name, Object x, int... indexes) {
            if (offline) {
                if (x == null || !x.getClass().isArray()) {
                    out.append(name);
                    for (int i : indexes) {
                        out.printf("[%d]", i);
                    }
                    out.append("=").append("" + x);
                    out.println();
                } else {
                    indexes = Arrays.copyOf(indexes, indexes.length + 1);
                    if (x instanceof byte[]) {
                        byte[] arr = (byte[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else if (x instanceof short[]) {
                        short[] arr = (short[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else if (x instanceof boolean[]) {
                        boolean[] arr = (boolean[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else if (x instanceof char[]) {
                        char[] arr = (char[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else if (x instanceof int[]) {
                        int[] arr = (int[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else if (x instanceof float[]) {
                        float[] arr = (float[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else if (x instanceof double[]) {
                        double[] arr = (double[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else if (x instanceof long[]) {
                        long[] arr = (long[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    } else {
                        Object[] arr = (Object[]) x;
                        for (int i = 0; i < arr.length; i++) {
                            indexes[indexes.length - 1] = i;
                            debug(name, arr[i], indexes);
                        }
                    }
                }
            }
            return this;
        }

    }

    static class Factorial {
        int[] fact;
        int[] inv;
        Modular modular;

        public Modular getModular() {
            return modular;
        }

        public Factorial(int[] fact, int[] inv, InverseNumber in, int limit, Modular modular) {
            this.modular = modular;
            this.fact = fact;
            this.inv = inv;
            fact[0] = inv[0] = 1;
            for (int i = 1; i <= limit; i++) {
                fact[i] = modular.mul(fact[i - 1], i);
                inv[i] = modular.mul(inv[i - 1], in.inv[i]);
            }
        }

        public Factorial(int limit, Modular modular) {
            this(new int[limit + 1], new int[limit + 1], new InverseNumber(limit, modular), limit, modular);
        }

        public int fact(int n) {
            return fact[n];
        }

        public int invFact(int n) {
            return inv[n];
        }

    }

    static class DSU {
        protected int[] p;
        protected int[] rank;
        int[] size;

        public DSU(int n) {
            p = new int[n];
            rank = new int[n];
            size = new int[n];
            reset();
        }

        public final void reset() {
            for (int i = 0; i < p.length; i++) {
                p[i] = i;
                rank[i] = 0;
                size[i] = 1;
            }
        }

        public final int find(int a) {
            if (p[a] == p[p[a]]) {
                return p[a];
            }
            return p[a] = find(p[a]);
        }

        public final void merge(int a, int b) {
            a = find(a);
            b = find(b);
            if (a == b) {
                return;
            }
            if (rank[a] == rank[b]) {
                rank[a]++;
            }

            if (rank[a] < rank[b]) {
                int tmp = a;
                a = b;
                b = tmp;
            }

            size[a] += size[b];
            p[b] = a;
        }

    }

    static class Modular {
        int m;

        public int getMod() {
            return m;
        }

        public Modular(int m) {
            this.m = m;
        }

        public Modular(long m) {
            this.m = (int) m;
            if (this.m != m) {
                throw new IllegalArgumentException();
            }
        }

        public Modular(double m) {
            this.m = (int) m;
            if (this.m != m) {
                throw new IllegalArgumentException();
            }
        }

        public int valueOf(int x) {
            x %= m;
            if (x < 0) {
                x += m;
            }
            return x;
        }

        public int valueOf(long x) {
            x %= m;
            if (x < 0) {
                x += m;
            }
            return (int) x;
        }

        public int mul(int x, int y) {
            return valueOf((long) x * y);
        }

        public int plus(int x, int y) {
            return valueOf(x + y);
        }

        public String toString() {
            return "mod " + m;
        }

    }

    static class SequenceUtils {
        public static boolean equal(int[] a, int al, int ar, int[] b, int bl, int br) {
            if ((ar - al) != (br - bl)) {
                return false;
            }
            for (int i = al, j = bl; i <= ar; i++, j++) {
                if (a[i] != b[j]) {
                    return false;
                }
            }
            return true;
        }

    }
}

