title: Calling a function within a switch case
body: <p>I have been trying to create a calculator or a semi calculator, I want to know what went wrong with my code and why? </p>
  
  <p>This is my code where I get errors while compiling it, in one machine I get different error while in other machine, the error is different . </p>
  
  <p>I hope you guys can help me sort it out.
  Its a small program to understand C programming little bit better.</p>
  
  <pre><code>#include&lt;stdio.h&gt;
  int main()
  {
      int operation,fc,v1,v2;
      double fcd;
      printf("input 2 values\n");
      scanf("%d%d",&amp;v1,&amp;v2);
      /* telling the user to choose any type of calculator */
        printf("please choose what you want to do with your values\n");
        printf("1- Sum\n");
        printf("2- substracttion\n"); 
        printf("3- multiplay\n");
        printf("4- devision\n"); 
        scanf("%d",&amp;operation);//input a
        switch(operation)
      {
        case 1:
        int fc = sum(int v1, int v2);
          printf("sum of two values = %d\n",fc);
          break;
  
      case 2:
         int fc = substact(int v1, int v2);
         printf("substract of two values = %d",fc);
          break;
  
      case 3:
          int fc = multiplay(int v1, int v2);
          printf("multiply of two values = %d\n",fc);
          break;
  
      case 4:
         int fcd = devision(int v1, int v2);
         printf("division of two values = %d\n",fc);
          break;
      default:
          printf("wrong choice\n");
      }
  return 0;}
  
  int sum(int a,int b)
  {
      int sum=0;
      um=a+b;
      return sum;
  }
  int substact(int a,int b)
  {
      int sub=0;
      sub=a-b;
      return sub;
  }
  int multiplay(int a,int b)
  {
      int mult=1;
      mult=a*b;
      return mult;
  }
  double devision(int a,int b)
  {
      double  devi=1;
      devi=a/b;
      return devi;
  }
  </code></pre>