#include <iostream> using namespace std; typedef unsigned long long ull; inline ull f(ull n){ ull sum = 0; while(n > 0){ sum += (n % 10) * (n % 10); n /= 10; } return sum; } int main(){ ull k, a, b; ull count = 0; cin >> k >> a >> b; ull i = a - a % k; if(i < a) i += k; for(; i <= b; i += k){ if(k * f(i) == i){ ++count; } } cout << count; 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 | #include <iostream> using namespace std; typedef unsigned long long ull; inline ull f(ull n){ ull sum = 0; while(n > 0){ sum += (n % 10) * (n % 10); n /= 10; } return sum; } int main(){ ull k, a, b; ull count = 0; cin >> k >> a >> b; ull i = a - a % k; if(i < a) i += k; for(; i <= b; i += k){ if(k * f(i) == i){ ++count; } } cout << count; return 0; } |