Calculadora Básica em C

peczenyj

http://www.java2s.com/Code/C/Small-Application/Calculator.htm

#include <stdio.h>



void main()

{

  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 %  */

  char answer = 0;                     /* Added to store answer for continuing  */



start:                                 /* Label added for goto destination */

   printf("\nEnter the calculation as number operator number\n&quot; /*Modified */

   scanf("%lf %c %lf", &number1, &operation, &number2);



  /* Code to check the input goes here */

  switch(operation)

  {

    case '+':                              /* No checks necessary for add       */

      printf("= %lf\n", number1 + number2);

      break;



    case '-':                               /* No checks necessary for subtract */

      printf("= %lf\n", number1 - number2);

      break;



    case '*':                               /* No checks necessary for multiply */

      printf("= %lf\n", number1 * number2);

      break;                              



    case '/':

      if(number2 == 0)                      /* Check second operand for zero    */

        printf("\n\n\aDivision by zero error!\n&quot;

    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&quot;

    else

      printf("= %ld\n", (long)number1 % (long)number2);

        break;



    default:                          /* Operation is invalid if we get to here */

      printf("\n\n\aIllegal operation!\n&quot;

  }

  /* The following statements added to prompt for continuing */ 

  printf("\n Do you want to do another calculation? (y or n): &quot;

  scanf(" %c", &answer);

  if(answer == 'y' || answer == 'Y')

    goto start;                       /* Go back to the beginning */

}

#include <stdio.h>



int main()

{

   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 %  */

   char answer = 0;                     /* Added to store answer for continuing  */



   char Fim = 0;

   do

   {

      printf("\nEnter the calculation as number operator number\n&quot; /*Modified */

      scanf("%lf %c %lf", &number1, &operation, &number2);

   

      /* Code to check the input goes here */

      switch(operation)

      {

         case '+':                              /* No checks necessary for add       */

            printf("= %lf\n", number1 + number2);

            break;

   

            case '-':                               /* No checks necessary for subtract */

               printf("= %lf\n", number1 - number2);

               break;

   

               case '*':                               /* No checks necessary for multiply */

                  printf("= %lf\n", number1 * number2);

                  break;

   

         case '/':

            if(number2 == 0)                      /* Check second operand for zero    */

               printf("\n\n\aDivision by zero error!\n&quot;

            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&quot;

               else

                  printf("= %ld\n", (long)number1 % (long)number2);

               break;

   

               default:                          /* Operation is invalid if we get to here */

                  printf("\n\n\aIllegal operation!\n&quot;

      }

      /* The following statements added to prompt for continuing */

      printf("\n Do you want to do another calculation? (y or n): &quot;

      scanf(" %c", &answer);

      if(answer != 'y' || answer != 'Y') Fim = 1;

         

   } while( Fim == 0 );



   return(0);

}

Rui_Carlos

até goto's ele usam 8O

Só reforçando... o uso GOTO é uma péssima prática de programação, só é aceitável (e necessário) em Assembly.