一年中的第几天

题目

一年中的第几天

 思路分析

1.substr函数分割字符串，stoi函数将字符串转为十进制

stoi函数介绍

substr函数介绍

2.判断是否为闰年，如果是闰年，则二月的天数+1

代码

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

int main()
{
	int months[13] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };
	string date;
	cin >> date;
	
	int year, month, day;
	year = stoi(date.substr(0, 4));
	month = stoi(date.substr(5, 2));
	day = stoi(date.substr(8, 2));
	//闰年
	if (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0))
	{
		months[2]++;
	}

	int sum = 0;

	for (int i = 1; i < month; i++)
	{
		sum += months[i];
	}

	cout << sum + day;

	return 0;
}

　力扣代码

class Solution {
public:
    int dayOfYear(string date) 
    {
        int months[13] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };
        int year, month, day;
        year = stoi(date.substr(0, 4));
        month = stoi(date.substr(5, 2));
        day = stoi(date.substr(8, 2));
        //闰年
        if (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0))
        {
            months[2]++;
        }

        int sum = 0;

        for (int i = 1; i < month; i++)
        {
            sum += months[i];
        }

        return sum + day;
    }
};