description: The Olympic Games have just started and Federico is eager to watch the marathon race.
  
  There will be n athletes, numbered from 1 to n, competing in the marathon, and all of them have taken part in 5 important marathons, numbered from 1 to 5, in the past. For each 1≤ i≤ n and 1≤ j≤ 5, Federico remembers that athlete i ranked r_{i,j}-th in marathon j (e.g., r_{2,4}=3 means that athlete 2 was third in marathon 4).
  
  Federico considers athlete x superior to athlete y if athlete x ranked better than athlete y in at least 3 past marathons, i.e., r_{x,j}<r_{y,j} for at least 3 distinct values of j.
  
  Federico believes that an athlete is likely to get the gold medal at the Olympics if he is superior to all other athletes.
  
  Find any athlete who is likely to get the gold medal (that is, an athlete who is superior to all other athletes), or determine that there is no such athlete.
  
  Input
  
  The first line contains a single integer t (1 ≤ t ≤ 1000) — the number of test cases. Then t test cases follow.
  
  The first line of each test case contains a single integer n (1≤ n≤ 50 000) — the number of athletes.
  
  Then n lines follow, each describing the ranking positions of one athlete.
  
  The i-th of these lines contains the 5 integers r_{i,1},\,r_{i,2},\,r_{i,3},\,r_{i,4},  r_{i,5} (1≤ r_{i,j}≤ 50 000) — the ranking positions of athlete i in the past 5 marathons. It is guaranteed that, in each of the 5 past marathons, the n athletes have distinct ranking positions, i.e., for each 1≤ j≤ 5, the n values r_{1,j},  r_{2, j},  ...,  r_{n, j} are distinct.
  
  It is guaranteed that the sum of n over all test cases does not exceed 50 000.
  
  Output
  
  For each test case, print a single integer — the number of an athlete who is likely to get the gold medal (that is, an athlete who is superior to all other athletes). If there are no such athletes, print -1. If there is more than such one athlete, print any of them.
  
  Example
  
  Input
  
  
  4
  1
  50000 1 50000 50000 50000
  3
  10 10 20 30 30
  20 20 30 10 10
  30 30 10 20 20
  3
  1 1 1 1 1
  2 2 2 2 2
  3 3 3 3 3
  6
  9 5 3 7 1
  7 4 1 6 8
  5 6 7 3 2
  6 7 8 8 6
  4 2 2 4 5
  8 3 6 9 4
  
  
  Output
  
  
  1
  -1
  1
  5
  
  Note
  
  Explanation of the first test case: There is only one athlete, therefore he is superior to everyone else (since there is no one else), and thus he is likely to get the gold medal.
  
  Explanation of the second test case: There are n=3 athletes. 
  
    * Athlete 1 is superior to athlete 2. Indeed athlete 1 ranks better than athlete 2 in the marathons 1, 2 and 3. 
    * Athlete 2 is superior to athlete 3. Indeed athlete 2 ranks better than athlete 3 in the marathons 1, 2, 4 and 5. 
    * Athlete 3 is superior to athlete 1. Indeed athlete 3 ranks better than athlete 1 in the marathons 3, 4 and 5. 
  
  
  
  Explanation of the third test case: There are n=3 athletes. 
  
    * Athlete 1 is superior to athletes 2 and 3. Since he is superior to all other athletes, he is likely to get the gold medal. 
    * Athlete 2 is superior to athlete 3. 
    * Athlete 3 is not superior to any other athlete. 
  
  
  
  Explanation of the fourth test case: There are n=6 athletes. 
  
    * Athlete 1 is superior to athletes 3, 4, 6. 
    * Athlete 2 is superior to athletes 1, 4, 6. 
    * Athlete 3 is superior to athletes 2, 4, 6. 
    * Athlete 4 is not superior to any other athlete. 
    * Athlete 5 is superior to athletes 1, 2, 3, 4, 6. Since he is superior to all other athletes, he is likely to get the gold medal. 
    * Athlete 6 is only superior to athlete 4. 
solution: 
  
  
  public class Main {
  
  	public static void main(String[] args) {
  		new Main();
  	}
  
  	public Main() {
  		FastScanner fs = new FastScanner();
  		java.io.PrintWriter out = new java.io.PrintWriter(System.out);
  		solve(fs, out);
  		out.flush();
  	}
  
  	public void solve(FastScanner fs, java.io.PrintWriter out) {
  		int t = fs.nextInt();
  		test: while(t --> 0) {
  			int n = fs.nextInt();
  			int[][] r = new int[5][n];
  			for (int i = 0;i < n;++ i) {
  				for (int j = 0;j < 5;++ j) {
  					r[j][i] = fs.nextInt();
  				}
  			}
  			int[] check = new int[n], check2 = new int[n];
  			for (int i = 0;i < n;++ i) check[i] = check2[i] = i;
  			Arrays.shuffle(check);
  			Arrays.shuffle(check2);
  			cont: for (int i : check) {
  				for (int j : check2) {
  					int win = 0;
  					for (int k = 0;k < 5;++ k) if (r[k][i] <= r[k][j]) ++ win;
  					if (win < 3) continue cont;
  				}
  				out.println(i + 1);
  				continue test;
  			}
  			out.println(-1);
  		}
  	}
  
  	final int MOD = 998_244_353;
  	int plus(int n, int m) {
  		int sum = n + m;
  		if (sum >= MOD) sum -= MOD;
  		return sum;
  	}
  	int minus(int n, int m) {
  		int sum = n - m;
  		if (sum < 0) sum += MOD;
  		return sum;
  	}
  	int times(int n, int m) {
  		return (int)((long)n * m % MOD);
  	}
  	int divide(int n, int m) {
  		return times(n, IntMath.pow(m, MOD - 2, MOD));
  	}
  	int[] fact, invf;
  	void calc(int len) {
  		len += 2;
  		fact = new int[len];
  		invf = new int[len];
  		fact[0] = fact[1] = invf[0] = invf[1] = 1;
  		for (int i = 2;i < fact.length;++ i) fact[i] = times(fact[i - 1], i);
  		invf[len - 1] = divide(1, fact[len - 1]);
  		for (int i = len - 1;i > 1;-- i) invf[i - 1] = times(i, invf[i]);
  	}
  	int comb(int n, int m) {
  		if (n < m) return 0;
  		return times(fact[n], times(invf[n - m], invf[m]));
  	}
  }
  
  class FastScanner {
  
  	private final java.io.InputStream in = System.in;
  	private final byte[] buffer = new byte[8192];
  	private int ptr = 0;
  	private int buflen = 0;
  
  	private boolean hasNextByte() {
  		if (ptr < buflen) return true;
  		ptr = 0;
  		try {
  			buflen = in.read(buffer);
  		} catch (java.io.IOException e) {
  			e.printStackTrace();
  		}
  		return buflen > 0;
  	}
  
  	private byte readByte() {
  		return hasNextByte() ? buffer[ptr++ ] : -1;
  	}
  
  	private static boolean isPrintableChar(byte c) {
  		return 32 < c || c < 0;
  	}
  
  	private static boolean isNumber(int c) {
  		return '0' <= c && c <= '9';
  	}
  
  	public boolean hasNext() {
  		while (hasNextByte() && !isPrintableChar(buffer[ptr]))
  			ptr++ ;
  		return hasNextByte();
  	}
  
  	public String next() {
  		if (!hasNext()) throw new java.util.NoSuchElementException();
  		StringBuilder sb = new StringBuilder();
  		byte b;
  		while (isPrintableChar(b = readByte()))
  			sb.appendCodePoint(b);
  		return sb.toString();
  	}
  
  	public final char nextChar() {
  		if (!hasNext()) throw new java.util.NoSuchElementException();
  		return (char)readByte();
  	}
  
  	public final long nextLong() {
  		if (!hasNext()) throw new java.util.NoSuchElementException();
  		long n = 0;
  		try {
  			byte b = readByte();
  			if (b == '-') {
  				while (isNumber(b = readByte()))
  					n = n * 10 + '0' - b;
  				return n;
  			} else if (!isNumber(b)) throw new NumberFormatException();
  			do
  				n = n * 10 + b - '0';
  			while (isNumber(b = readByte()));
  		} catch (java.util.NoSuchElementException e) {}
  		return n;
  	}
  
  	public final int nextInt() {
  		if (!hasNext()) throw new java.util.NoSuchElementException();
  		int n = 0;
  		try {
  			byte b = readByte();
  			if (b == '-') {
  				while (isNumber(b = readByte()))
  					n = n * 10 + '0' - b;
  				return n;
  			} else if (!isNumber(b)) throw new NumberFormatException();
  			do
  				n = n * 10 + b - '0';
  			while (isNumber(b = readByte()));
  		} catch (java.util.NoSuchElementException e) {}
  		return n;
  	}
  
  	public double nextDouble() {
  		return Double.parseDouble(next());
  	}
  }
  
  class Arrays {
  
  	public static void sort(final int[] array) {
  		sort(array, 0, array.length);
  	}
  
  	public static void sort(final int[] array, int fromIndex, int toIndex) {
  		if (toIndex - fromIndex  <= 512) {
  			java.util.Arrays.sort(array, fromIndex, toIndex);
  			return;
  		}
  		sort(array, fromIndex, toIndex, 0, new int[array.length]);
  	}
  
  	private static final void sort(int[] a, final int from, final int to, final int l, final int[] bucket) {
  		if (to - from  <= 512) {
  			java.util.Arrays.sort(a, from, to);
  			return;
  		}
  		final int BUCKET_SIZE = 256;
  		final int INT_RECURSION = 4;
  		final int MASK = 0xff;
  		final int shift = l << 3;
  		final int[] cnt = new int[BUCKET_SIZE + 1];
  		final int[] put = new int[BUCKET_SIZE];
  		for (int i = from; i < to; i++) ++ cnt[(a[i] >>> shift & MASK) + 1];
  		for (int i = 0; i < BUCKET_SIZE; i++) cnt[i + 1] += cnt[i];
  		for (int i = from; i < to; i++) {
  			int bi = a[i] >>> shift & MASK;
  			bucket[cnt[bi] + put[bi]++] = a[i];
  		}
  		for (int i = BUCKET_SIZE - 1, idx = from; i >= 0; i--) {
  			int begin = cnt[i];
  			int len = cnt[i + 1] - begin;
  			System.arraycopy(bucket, begin, a, idx, len);
  			idx += len;
  	    }
  		final int nxtL = l + 1;
  		if (nxtL < INT_RECURSION) {
  			sort(a, from, to, nxtL, bucket);
  			if (l == 0) {
  				int lft, rgt;
  				lft = from - 1; rgt = to;
  				while (rgt - lft > 1) {
  					int mid = lft + rgt >> 1;
  					if (a[mid] < 0) lft = mid;
  					else rgt = mid;
  				}
  				reverse(a, from, rgt);
  				reverse(a, rgt, to);
  	        }
  	    }
  	}
  
  	public static void sort(final long[] array) {
  		sort(array, 0, array.length);
  	}
  
  	public static void sort(final long[] array, int fromIndex, int toIndex) {
  		if (toIndex - fromIndex  <= 512) {
  			java.util.Arrays.sort(array, fromIndex, toIndex);
  			return;
  		}
  		sort(array, fromIndex, toIndex, 0, new long[array.length]);
  	}
  
  	private static final void sort(long[] a, final int from, final int to, final int l, final long[] bucket) {
  		final int BUCKET_SIZE = 256;
  		final int LONG_RECURSION = 8;
  		final int MASK = 0xff;
  		final int shift = l << 3;
  		final int[] cnt = new int[BUCKET_SIZE + 1];
  		final int[] put = new int[BUCKET_SIZE];
  		for (int i = from; i < to; i++) ++ cnt[(int) ((a[i] >>> shift & MASK) + 1)];
  		for (int i = 0; i < BUCKET_SIZE; i++) cnt[i + 1] += cnt[i];
  		for (int i = from; i < to; i++) {
  			int bi = (int) (a[i] >>> shift & MASK);
  			bucket[cnt[bi] + put[bi]++] = a[i];
  		}
  		for (int i = BUCKET_SIZE - 1, idx = from; i >= 0; i--) {
  			int begin = cnt[i];
  			int len = cnt[i + 1] - begin;
  			System.arraycopy(bucket, begin, a, idx, len);
  			idx += len;
  	    }
  		final int nxtL = l + 1;
  		if (nxtL < LONG_RECURSION) {
  			sort(a, from, to, nxtL, bucket);
  			if (l == 0) {
  				int lft, rgt;
  				lft = from - 1; rgt = to;
  				while (rgt - lft > 1) {
  					int mid = lft + rgt >> 1;
  					if (a[mid] < 0) lft = mid;
  					else rgt = mid;
  				}
  				reverse(a, from, rgt);
  				reverse(a, rgt, to);
  	        }
  	    }
  	}
  
  	public static void reverse(int[] array) {
  		reverse(array, 0, array.length);
  	}
  
  	public static void reverse(int[] array, int fromIndex, int toIndex) {
  		for (-- toIndex;fromIndex < toIndex;++ fromIndex, -- toIndex) {
  			int swap = array[fromIndex];
  			array[fromIndex] = array[toIndex];
  			array[toIndex] = swap;
  		}
  	}
  
  	public static void reverse(long[] array) {
  		reverse(array, 0, array.length);
  	}
  
  	public static void reverse(long[] array, int fromIndex, int toIndex) {
  		for (-- toIndex;fromIndex < toIndex;++ fromIndex, -- toIndex) {
  			long swap = array[fromIndex];
  			array[fromIndex] = array[toIndex];
  			array[toIndex] = swap;
  		}
  	}
  
  	public static void shuffle(int[] array) {
  		java.util.Random rnd = new java.util.Random();
  		for (int i = 0;i < array.length;++ i) {
  			int j = rnd.nextInt(array.length - i) + i;
  			int swap = array[i];
  			array[i] = array[j];
  			array[j] = swap;
  		}
  	}
  
  	public static void shuffle(long[] array) {
  		java.util.Random rnd = new java.util.Random();
  		for (int i = 0;i < array.length;++ i) {
  			int j = rnd.nextInt(array.length - i) + i;
  			long swap = array[i];
  			array[i] = array[j];
  			array[j] = swap;
  		}
  	}
  }
  
  class IntMath {
  
  	public static int gcd(int a, int b) {
  		while (a != 0)
  			if ((b %= a) != 0) a %= b;
  			else return a;
  		return b;
  	}
  
  	public static int gcd(int... array) {
  		int ret = array[0];
  		for (int i = 1; i < array.length; ++i)
  			ret = gcd(ret, array[i]);
  		return ret;
  	}
  
  	public static long gcd(long a, long b) {
  		while (a != 0)
  			if ((b %= a) != 0) a %= b;
  			else return a;
  		return b;
  	}
  
  	public static long gcd(long... array) {
  		long ret = array[0];
  		for (int i = 1; i < array.length; ++i)
  			ret = gcd(ret, array[i]);
  		return ret;
  	}
  
  	public static long lcm(long a, long b) {
  		return a / gcd(a, b) * b;
  	}
  
  	public static int pow(int a, int b) {
  		int ans = 1;
  		for (int mul = a; b > 0; b >>= 1, mul *= mul)
  			if ((b & 1) != 0) ans *= mul;
  		return ans;
  	}
  
  	public static long pow(long a, long b) {
  		long ans = 1;
  		for (long mul = a; b > 0; b >>= 1, mul *= mul)
  			if ((b & 1) != 0) ans *= mul;
  		return ans;
  	}
  
  	public static int pow(int a, long b, int mod) {
  		if (b < 0) b = b % (mod - 1) + mod - 1;
  		long ans = 1;
  		for (long mul = a; b > 0; b >>= 1, mul = mul * mul % mod)
  			if ((b & 1) != 0) ans = ans * mul % mod;
  		return (int)ans;
  	}
  
  	public static int pow(long a, long b, int mod) {
  		return pow((int)(a % mod), b, mod);
  	}
  
  	public static int floorsqrt(long n) {
  		return (int)Math.sqrt(n + 0.1);
  	}
  
  	public static int ceilsqrt(long n) {
  		return n <= 1 ? (int)n : (int)Math.sqrt(n - 0.1) + 1;
  	}
  }
  