#include<stdio.h>int main(){int year,month,day;int i,sum=0;int buf[12]={31,28,31,30,31,30,31,31,30,31,30,31};printf(&quot;please input year month day\n&quot;);scanf(&quot;%d %d %d&quot;,&amp;year,&amp;month,&amp;day);for(i=0;i<month-1;i++){sum+=buf[i];}sum=sum+day;if((month>2)&amp;&amp;(year%4==0&amp;&amp;year%100!=0)||(year%400==0)){sum+=1;}printf(&quot;输入的日期对应的是第%d天&quot;,sum);return 0;}