#include <iostream> #include <algorithm> int calcDigitsNumber(long long int number) { unsigned long long int checker = 10; int result = 1; while (checker <= number){ checker *= 10; ++result; } return result; } int calcSumOfSquareDigits(long long int number) { int result = 0; while (number > 0){ int rem = (number % 10); result += rem*rem; number /= 10; } return result; } int main() { long long int k, a, b; std::cin >> k >> a >> b; int digitsA = calcDigitsNumber(a); int digitsB = calcDigitsNumber(b); long long int minv = std::max(k*digitsA, a); long long int maxv = std::min(k * 81 * digitsB, b); long long int remainder = minv%k; if (remainder != 0) minv += k - remainder; long long int val = minv; int result = 0; while (val <= maxv){ if (k*calcSumOfSquareDigits(val) == val){ ++result; } val += k; } std::cout << result << std::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 49 50 51 52 53 54 55 | #include <iostream> #include <algorithm> int calcDigitsNumber(long long int number) { unsigned long long int checker = 10; int result = 1; while (checker <= number){ checker *= 10; ++result; } return result; } int calcSumOfSquareDigits(long long int number) { int result = 0; while (number > 0){ int rem = (number % 10); result += rem*rem; number /= 10; } return result; } int main() { long long int k, a, b; std::cin >> k >> a >> b; int digitsA = calcDigitsNumber(a); int digitsB = calcDigitsNumber(b); long long int minv = std::max(k*digitsA, a); long long int maxv = std::min(k * 81 * digitsB, b); long long int remainder = minv%k; if (remainder != 0) minv += k - remainder; long long int val = minv; int result = 0; while (val <= maxv){ if (k*calcSumOfSquareDigits(val) == val){ ++result; } val += k; } std::cout << result << std::endl; return 0; } |