题解 | #今年的第几天？#

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

//每个月的天数
int dayOfMonth[2][13] = {
    {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
    {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
};
int runyear(int n){
	if(n%400==0||(n%4==0&&n%100!=0)){
		return 1;
	}
	return 0;
}
int main(){
	int y,m,d;
	scanf("%d %d %d",&y,&m,&d);
	int sum=0;
	for(int i=1;i<m;i++){//第m个月还没过完，所以先不算m 
		sum+=dayOfMonth[runyear(y)][i];
	}
	sum+=d;
	cout<<sum<<endl;
	return 0;
}