题解 | 计算一年中的第几天

C++

#include <iostream>
using namespace std;

int main() {
    int y, m, d;
    while (cin >> y >> m >> d) {
        switch (m) {
            case 1: break;
            case 2: d+=31; break;
            case 3: d+=59; break; // 默认28天
            case 4: d+=90; break;
            case 5: d+=120; break;
            case 6: d+=151; break;
            case 7: d+=181; break;
            case 8: d+=212; break;
            case 9: d+=243; break;
            case 10: d+=273; break;
            case 11: d+=304; break;
            case 12: d+=334; break;
        }
        if (y%4==0) d+=1;
        cout << d << endl;
    }
}
// 64 位输出请用 printf("%lld")