题解 | 日期差值

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
using namespace std;
int daymonth[13] = { 0,31,29,31,30,31,30,31,31,30,31,30,31 };
int leapyear(int year)
{
	return (year % 4 == 0 && year % 100 != 0 || year % 400 == 0);
}
int abs(int a,int b)
{
	if (a - b < 0)
	{
		return b - a;
	}
	else return a - b;
}
int fmin(int a, int b)
{
	if (a < b)
	{
		return a;
	}
	else return b;
}
int fmax(int a, int b)
{
	if (a > b)
	{
		return a;
	}
	else return b;
}
int main()
{
	int number1, number2;
	int year1, year2, month1, month2, day1, day2;
	while (scanf("%d%d", &number1,&number2) != EOF)
	{
		year1 = number1 / 10000;
		year2 = number2 / 10000;
		day1 = number1 % 100;
		day2 = number2 % 100;
		month1 = ((number1 - day1) % 10000) / 100;
		month2 = ((number2 - day1) % 10000) / 100;
		int num1 = 0;
		int num2 = 0;
		int number = 0;
		int temp1 = fmax(year1, year2);
		int temp2 = fmin(year1, year2);
		while (temp1 != temp2)
		{
			if (leapyear(temp2))
			{
				number += 366;
			}
			else number += 365;
			temp2++;
		}
		if (leapyear(fmax(year1, year2)))
		{
			daymonth[2] = 29;
		}
		else daymonth[2] = 28;
		for (int i = 0; i < month1; i++)
		{
			num1 += daymonth[i];
		}
		num1 += day1;
		for (int j = 0; j < month2; j++)
		{
			num2 += daymonth[j];
		}
		num2 += day2;
		if (year1 < year2)
		{
			number += num2 - num1 + 1;
		}
		else if (year2 < year1)
		{
			number += num1 - num2 + 1;
		}
		else number += abs(num1,num2) + 1;
		printf("%d\n", number);
	}
	return 0;
}