#include <iostream> using namespace std; int main() { int ans = 0; for (int a = 1; a <= 9; ++a) for (int b = 1; b <= 9; ++b) if (b != a) for (int c = 1; c <= 9; ++c) if (c != a && c != b) for (int d = 1; d <= 9; ++d) if (d != a && d != b && d != c) for (int e = 1; e <= 9; ++e) if (e != a && e != b && e != c && e != d) { long long left = (10LL * a + b) * (100LL * c + 10LL * d + e); long long right = (100LL * a + 10LL * d + b) * (10LL * c + e); if (left == right) ++ans; } cout << ans << endl; return 0; } /************************************************************** Problem: 1257 User: admin Language: C++ Result: Runtime Error ****************************************************************/