题解 | #计算日期到天数转换#

#include <bits/stdc++.h>
using namespace std;

bool isrich(int x){
    if(((x %4 == 0) && (x % 100 != 0)) || x % 400 == 0){
        return true;
    }
    return false;
}

int main(){
    int y, m, d;
    cin >> y >> m >> d;
    bool flag = isrich(y);
    vector<int> vec = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    for(int i = 1; i <= 12; i++){
        vec[i] += vec[i-1];
    }
    int num = vec[m-1] + d;
    if(flag && m > 2) num++;
    cout << num << endl;
    return 0;
}