#include <stdio.h> int main() { char ch = 0; double a,b; scanf("%lf%c%lf",&a,&ch,&b); if(ch == '+'||ch == '-'||ch == '*'||ch == '/') { if(ch == '+') printf("%.4lf+%.4lf=%.4lf",a,b,a+b); else if(ch == '-') prin...