#include<stdio.h>
void sum_diff(float op1,float op2,float *psum,float *pdiff);

int main(void)
{
    float op1,op2,sum,diff;
    printf("input op1 and op2:");
    scanf("%2f%2f",&op1,&op2);
    sum_diff(op1,op2,&sum,&diff);
    printf("%2f+%2f=%2f,%2f-%2f=%2f\n",op1,op2,sum,op1,op2,diff);
    
    return 0;
} 
void sum_diff(float op1,float op2,float *psum,float *pdiff)
{
    *psum=op1+op2;
    *pdiff=op1-op2;
}

#include<stdio.h>
int main()
{
    void findmax(int *px,int *py,int *pmax);
    int x1,x2,max=0;
    printf("输入px,py:");
    scanf("%d%d",&x1,&x2);
    findmax(&x1,&x2,&max);
    printf("max=%d\n",max);
    return 0;
}
void findmax(int *px,int *py,int *pmax)
{
    if(*px<*py){
        *pmax=*py;
    }
    else
    *pmax=*px;
return 0；
}