1801.cpp

// Ivan Carvalho
// Solution to https://www.beecrowd.com.br/judge/problems/view/1801
#include <cstdio>
#include <cstring>
#define MAXN 10
typedef long long ll;
ll x, y, auxiliar;
int frequencia[MAXN], referencia[MAXN], resposta, digitos, digitos_auxiliar;
const ll MAXIMO = 1e13 + 1;
int main() {
    scanf("%lld", &x);
    auxiliar = x;
    while (auxiliar > 0) {
        referencia[auxiliar % 10]++;
        auxiliar /= 10;
        digitos++;
    }
    for (ll n = 1; n * n <= MAXIMO; n++) {
        y = n * n - x;
        if (y <= 0LL) continue;
        digitos_auxiliar = 0;
        memset(frequencia, 0, sizeof(frequencia));
        bool flag = false;
        auxiliar = y;
        while (auxiliar > 0) {
            frequencia[auxiliar % 10]++;
            auxiliar /= 10;
            digitos_auxiliar++;
        }
        if (digitos_auxiliar > digitos) break;
        for (int i = 0; i < MAXN; i++) {
            if (frequencia[i] != referencia[i]) {
                flag = true;
                break;
            }
        }
        if (flag) continue;
        resposta++;
    }
    printf("%d\n", resposta);
    return 0;
}