混乘数字 参考代码

#include <bits/stdc++.h>
using namespace std;

typedef long long LL;
int ans;
LL p[20];

LL getHash(int x, int y) {
    LL ret = 0;
    while (x != 0) {
        ret += p[x % 10];
        x /= 10;
    }
    while (y != 0) {
        ret += p[y % 10];
        y /= 10;
    }
    return ret;
}

bool judge(int x) {
    LL xHash = getHash(x, 0);
    for (int i = 2; i <= x / i; ++i) {
        if (x % i == 0) {
            if (getHash(i, x / i) == xHash) {
                return true;
            }
        }
    }
    return false;
}

int main() {
#ifdef ExRoc
    freopen("test.txt", "r", stdin);
#endif // ExRoc
    ios::sync_with_stdio(false);

    p[0] = 1;
    for (int i = 1; i < 10; ++i) {
        p[i] = p[i - 1] * 10;
    }
    for (int i = 1; i <= 1000000; ++i) {
        if (judge(i)) {
            ++ans;
        }
    }
    cout << ans << endl;
//    cout << 590 << endl;

    return 0;
}