代码：

#include "stdafx.h"

int _tmain(int argc, _TCHAR* argv[])
{
int up1,down1,up2,down2;

do{  
    printf("Enter two fractions seperated by a plus sign:");  
    scanf("%d/%d+%d/%d",&up1,&down1,&up2,&down2);  
    int down3=down1\*down2;  
    int up3=up1\*down2+up2\*down1;

    int small=(up3<down3)?up3:down3;  
    int gcd;  
    for(;small>;small--){  
        if(up3%small== && down3%small==)  
        {  
            gcd=small;  
            break;  
        }  
    }

    printf("The sum is %d/%d\\n",up3/gcd,down3/gcd);  
}while(up1!=);

return ;  

}

代码：

Enter two fractions seperated by a plus sign:/+/
The sum is /
Enter two fractions seperated by a plus sign:/+/
The sum is /
Enter two fractions seperated by a plus sign:/+/
The sum is /
Enter two fractions seperated by a plus sign:/+/
The sum is /
Enter two fractions seperated by a plus sign:/+/
The sum is /

--2020年6月9日--