二进制中1的个数有更优的解法，但是还是显示AC 0% #include <iostream> using namespace std; int DecSum(int i) { int sum = 0; while (i) { sum = sum + i % 10; i /= 10; } return sum; } int BinSum(int i) { int count = 0; while (i) { if (i & 1) count++; i = i >> 1; } return count; } int getRt(int i) { int num = 0; for (int index = 1; index <= i; index++) { if (BinSum(index) == DecSum(index)) { num++; } } return num; } int main() { int input = 0; while (cin>>input) { int rt = getRt(input); cout << rt << endl; } return 0; }