蓝桥杯历届试题之高斯笔记

#include<stdio.h>


bool rn(int n){
	if(n%4==0&&n%100!=0||n%400==0){
		return 1;
	}
	else return 0;
}

int main(){
	int yy=1777,mm=4,dd=30,ans;
	int day[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};
	scanf("%d",&ans);
	for(int i=4;i<=11;i++){
		ans=ans-day[i];
		mm++;
	}
	ans=ans-2;
	yy=1778;
	mm=1;
	dd=1;
	
	while(ans>=366){
		if(rn(yy+1)){ans=ans-366;
		yy++;
		}
		else{ans=ans-365;
		yy++;
		}
	}
	while(ans>=day[mm]){
		ans=ans-day[mm];
		mm++;
		if(mm==13){
			mm=1;
			yy++;
		}
	}
	while(ans){
	ans--;
	dd++;
	if(dd>day[mm]){
		dd=0;
		mm++;
		if(mm==13){
			mm=0;
			yy++;
		}
	}
	}
	printf("%d-",yy);
	if(mm<10) printf("0%d-",mm);
	else printf("%d-",mm);
	printf("%d",dd);
	return 0; 
	
}