C语言:在主函数中输入x,y,调用函数求出X,y的和,差,商,积,并在主函数中...答:include<stdio.h> int add(int a,int b){ return a+b;} int sub(int a,int b){ return a-b;} int mul(int a,int b){ return a*b;} float divi(int a,int b){ return 1.0*a/b;} void main(){ int x,y;scanf("%d%d",&x,&y);printf("x+y=%d\n",add(x,y));p...