#include <bits/stdc++.h> using namespace std; typedef long long int LL; LL digitSquaresSum(LL n) { LL ret = 0; while (n > 0) { ret += (n%10) * (n%10); n /= 10; } return ret; } LL solve(LL mx, LL k) { LL ret = 0; for (LL i = 0; i < 1800; i++) { LL n = i * k; if (n <= mx) { if (digitSquaresSum(n) == i) ret++; } } return ret; } int main() { LL k, a, b; scanf("%lld%lld%lld", &k, &a, &b); printf("%lld\n", solve(b, k) - solve((a-1), k)); return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 | #include <bits/stdc++.h> using namespace std; typedef long long int LL; LL digitSquaresSum(LL n) { LL ret = 0; while (n > 0) { ret += (n%10) * (n%10); n /= 10; } return ret; } LL solve(LL mx, LL k) { LL ret = 0; for (LL i = 0; i < 1800; i++) { LL n = i * k; if (n <= mx) { if (digitSquaresSum(n) == i) ret++; } } return ret; } int main() { LL k, a, b; scanf("%lld%lld%lld", &k, &a, &b); printf("%lld\n", solve(b, k) - solve((a-1), k)); return 0; } |