BOJ 24421 - 掛け算 (Multiplication) [C++]

문제

링크

풀이

#include <iostream>
#include <vector>
using namespace std;
 
void solve(void) {
  int n; cin >> n;
  vector<int> a(n);
  for (int i=0; i<n; i++) cin >> a[i];
 
  int ans = 0;
  for (int i=0; i<n-2; i++) for (int j=i+1; j<n-1; j++) for (int k=j+1; k<n; k++) {
    if (a[i] * a[j] == a[k]) ans++;
  }
  cout << ans;
}
 
int main(void) {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
 
  solve();
  return 0;
}