Read two numbers and one operators.
Conduct the operation based on the operator.
Check Division by zero error
Use switch statement to check the operator.
#include <stdio.h> int main(void) { double number1 = 0.0; /* First operand value a decimal number */ double number2 = 0.0; /* Second operand value a decimal number */ char operation = 0; /* Operation - must be +, -, *, /, or % */ printf("\nEnter the calculation\n"); scanf("%lf %c %lf", &number1, &operation, &number2); switch(operation) {//from w w w . j a va2s . c o m case '+': printf("= %lf\n", number1 + number2); break; case '-': printf("= %lf\n", number1 - number2); break; case '*': printf("= %lf\n", number1 * number2); break; case '/': if(number2 == 0) printf("\n\n\aDivision by zero error!\n"); else printf("= %lf\n", number1 / number2); break; case '%': // Check second operand for zero if((long)number2 == 0) printf("\n\n\aDivision by zero error!\n"); else printf("= %ld\n", (long)number1 % (long)number2); break; default: // Operation is invalid if we get to here printf("\n\n\aIllegal operation!\n"); break; } return 0; }