2080.txt

北大ACM题目例程 详细的解答过程 程序实现 算法分析

#include <stdio.h>
#include <math.h>
#include <stdlib.h> 

char *dow[]={"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
int month[]={ 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

int main()
{
	int i, j, n, y, m, d, h, s;
	while(1)
	{
		scanf( "%d", &n );
		if( n < 0 ) break;

		y = 2000, m=0, d=1;

		s = 0;
		for( i = 0;  ; i++ )
		{
			if( i%4 == 0 && ( i%100 != 0 || i%400 == 0 ) )
				month[1] = 29;
			else month[1] = 28;
			
			for( j=0; j<12; j++ )
			{
				s += month[j];
				if( s >= n+1 )
				{
					s -= month[j];
					break;
				}
			}
			if(  j < 12 ) break;
		}

		printf( "%04d-%02d-%02d %s\n", i+2000, j+1, n+1-s, dow[(n+6)%7] );
	}

	return 0;
}