12个高矮不同的人排成两排

#include <iostream>using namespace std;int bit_cnt(int n){ int result = 0; for (; n; n &= n-1, ++result); return result;}int main(){ int F[6], B[6]; int ans = 0; for (int state = 0; state < (1 << 12); ++state) if (bit_cnt(state) == 6) { int i = 0, j = 0; for (int k = 0; k < 12; ++k) if (state&(1<<k)) F[i++] = k; else B[j++] = k; int ok = 1; for (int k = 0; k < 6; ++k) if (B[k] < F[k]) {ok = 0; break;} ans += ok; } cout << ans << endl; return 0;}