#include<stdio.h>
int main()
{
    int year,month,day,s=0,i,d;
while(scanf("%d/%d/%d",&year,&month,&day)!=EOF){
    int m[14]={0,31,28,31,30,31,30,31,31,30,31,30,31};
    if(year%4==0&&year%100!=0||year%400==0)
    m[2]=29;
    else
    m[2]=28;
    for(i=0;i<month;++i)
    {
        s=s+m[i];
    }
    d=s+day;
    printf("%d\n",d);
}
}

        s=0; //初始化
        for(i=0; i<month; ++i)

#include<stdio.h>
int main()
{
    int year,month,day,s=0,i,d;
while(scanf("%d/%d/%d",&year,&month,&day)!=EOF){
    int m[14]={0,31,28,31,30,31,30,31,31,30,31,30,31};
    if(year%4==0&&year%100!=0||year%400==0)
    m[2]=29;
    else
    m[2]=28;
    for(i=0;i<month;++i)
    {
        s=s+m[i];
    }
    d=s+day;
    printf("%d\n",d);
    d=0;   //d清零
    s=0;    //s清零
}
}

这是为什么啊

不清零下一次输入会用回上一次保留的数据~