#include <stdio.h> long long calc(long long k) { long long ret = 0; while (k) { ret += (k % 10) * (k % 10); k /= 10; } return ret; } long long pp(long long a, long long b) { long long ret = 1; while (b--) ret *= a; return ret; } int main() { long long k, a, b; long long ans = 0; scanf("%lli %lli %lli", &k, &a, &b); //For i = 0 special case for (int i = 1; i < 10; ++i) { if (i >= a && i <= b && k * calc(i) == i) ++ans; } for (long long i = 1; i < 19; ++i) { long long start = pp (10, i); long long end = start * 10 - 1; if (start > b || end < a) continue; long long min_k = start / (i * 81); if (k < min_k) continue; long long val = start; if (start % k != 0) val = val - start % k + k; for (; val <= end; val += k) { if (val >= a && val <= b && k * calc(val) == val) { ++ans; } } } printf("%lli\n", ans); 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 54 55 56 57 58 59 60 61 62 63 64 65 66 67 | #include <stdio.h> long long calc(long long k) { long long ret = 0; while (k) { ret += (k % 10) * (k % 10); k /= 10; } return ret; } long long pp(long long a, long long b) { long long ret = 1; while (b--) ret *= a; return ret; } int main() { long long k, a, b; long long ans = 0; scanf("%lli %lli %lli", &k, &a, &b); //For i = 0 special case for (int i = 1; i < 10; ++i) { if (i >= a && i <= b && k * calc(i) == i) ++ans; } for (long long i = 1; i < 19; ++i) { long long start = pp (10, i); long long end = start * 10 - 1; if (start > b || end < a) continue; long long min_k = start / (i * 81); if (k < min_k) continue; long long val = start; if (start % k != 0) val = val - start % k + k; for (; val <= end; val += k) { if (val >= a && val <= b && k * calc(val) == val) { ++ans; } } } printf("%lli\n", ans); return 0; } |