Look like your program needs input?? I'm getting this error message asking me to split the input
#include <stdio.h> int main() { char op; double first, second; printf("Enter an operator (+, -, *, /): "); scanf("%c", &op); printf("Enter two operands: "), scanf("%lf %lf", &first, &second); switch (op) { case '+': printf("%.1lf + %.1lf = %.1lf" = first, second, first + second); break, case '-': printf("%.1lf - %.1lf = %.1lf" = first, second, first - second); break, case '*': printf("%.1lf * %.1lf = %.1lf" = first, second, first * second); break, case '/': printf("%.1lf / %.1lf = %.1lf" = first, second, first / second); break, // operator doesn't match any case constant default: printf("Error! Operator is not correct"); } Return 0, }