func_code_string: #include <bits/stdc++.h>   using namespace std;   int n;   int cnt[10000001] = {};   int par[10000001], ra[10000001];   void dsuInit() {     for (int i = 0; i < (int)(10000001); ++i) par[i] = i, ra[i] = cnt[i];   }   int dsuParent(int v) {     if (v == par[v]) return v;     return par[v] = dsuParent(par[v]);   }   void dsuMerge(int u, int v) {     u = dsuParent(u);     v = dsuParent(v);     if (u == v) return;     if (ra[u] < ra[v]) swap(u, v);     par[v] = u;     ra[u] += ra[v];   }   int gcd(int a, int b) {     while (b) a %= b, swap(a, b);     return a;   }   int main() {     scanf( %d , &n);     for (int i = 0; i < (int)(n); ++i) {       int x;       scanf( %d , &x);       ++cnt[x];     }     dsuInit();     for (int p = 1; p <= 3200; ++p) {       for (int q = p + 1; 2 * p * q <= 10000000; q += 2) {         if (gcd(p, q) != 1) continue;         long long x = (long long)q * q - p * p;         long long y = 2 * p * q;         long long z = p * p + (long long)q * q;         if (x <= 10000000 && y <= 10000000 && cnt[x] && cnt[y]) dsuMerge(x, y);         if (x <= 10000000 && z <= 10000000 && cnt[x] && cnt[z]) dsuMerge(x, z);         if (y <= 10000000 && z <= 10000000 && cnt[y] && cnt[z]) dsuMerge(y, z);       }     }     int ans = 0;     for (int i = 0; i < (int)(10000001); ++i)       if (cnt[i] && dsuParent(i) == i) {         if (ra[i] == cnt[i])           ans += cnt[i];         else           ++ans;       }     printf( %d n , ans);     return 0;   }   