#include <stdint.h> #include <iostream> #include <algorithm> using namespace std; int64_t sqsum(int64_t i) { int r = 0; while(i) { int d = i % 10; i /= 10; r += d * d; } return r; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); int64_t a, b, k; cin >> k >> a >> b; int d = 0; int64_t m = 0; while(81 * d >= m / k and m <= b / 9) { d += 1; m = 10 * m + 1; } b = min(b, 9 * m); b = min(b, 1458 * k); if(a > b) { cout << "0\n"; return 0; } int i0 = (a + k - 1) / k; int i1 = b / k; int r = 0; for(int i = i0; i < i1; ++i) { if(i == sqsum(k * i)) ++r; } cout << r << '\n'; 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 49 50 51 52 53 | #include <stdint.h> #include <iostream> #include <algorithm> using namespace std; int64_t sqsum(int64_t i) { int r = 0; while(i) { int d = i % 10; i /= 10; r += d * d; } return r; } int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); int64_t a, b, k; cin >> k >> a >> b; int d = 0; int64_t m = 0; while(81 * d >= m / k and m <= b / 9) { d += 1; m = 10 * m + 1; } b = min(b, 9 * m); b = min(b, 1458 * k); if(a > b) { cout << "0\n"; return 0; } int i0 = (a + k - 1) / k; int i1 = b / k; int r = 0; for(int i = i0; i < i1; ++i) { if(i == sqsum(k * i)) ++r; } cout << r << '\n'; return 0; } |