#include <iostream> #include <cmath> #include <algorithm> using namespace std; long long k, a, b; int getSum(long long n) { int sum = 0; while (n) { sum += (n % 10) * (n % 10); n /= 10; } return sum; } int main() { ios_base::sync_with_stdio(0); cin >> k >> a >> b; int total = 0; long long limits[20]; for (int i = 0; i < 20; i++) { limits[i] = 81 * i; limits[i] *= k; } limits[0] = 1; long long start = min((long long)ceil((double)a / k) * k, b); int maks = ceil(log10(b)); b = max(min(b, limits[maks]),start); for (long long i = start; i <= b; i += k) { if (getSum(i) * k == i) total++; } cout << total << endl; 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 35 36 37 38 39 40 41 42 43 44 45 46 47 48 | #include <iostream> #include <cmath> #include <algorithm> using namespace std; long long k, a, b; int getSum(long long n) { int sum = 0; while (n) { sum += (n % 10) * (n % 10); n /= 10; } return sum; } int main() { ios_base::sync_with_stdio(0); cin >> k >> a >> b; int total = 0; long long limits[20]; for (int i = 0; i < 20; i++) { limits[i] = 81 * i; limits[i] *= k; } limits[0] = 1; long long start = min((long long)ceil((double)a / k) * k, b); int maks = ceil(log10(b)); b = max(min(b, limits[maks]),start); for (long long i = start; i <= b; i += k) { if (getSum(i) * k == i) total++; } cout << total << endl; return 0; } |