#include<conio.h>
#include<stdlib.h>
#include<stdio.h>

int suma (int, int);
int resta (int, int);
int multi (int, int);

main (){

int n1, n2, op;
        do {

        printf("\tMenu");
        printf("\n1.-Sumar");
        printf("\n2.-Restar");
        printf("\n3.-Multiplicar");
        printf("\n4.-Salir\n");
        scanf("%d",&op);
        if(op < 3){
              printf("\nIntroduzca el numero A: ");
              scanf("%d", &n1);
              printf("\nIntroduzca el numero B: ");
              scanf("%d", &n2);
              }
        switch (op)
		    {
                   case 1: return=suma (n1, n2);break;
                   case 2: resta (n1, n2);break;
                   case 3: multi (n1, n2);break;
                   case 4: printf("\nGracias por usar Watagatapitusberry\n");break;
                   }
        if(op > 4){
               printf ("\nOpcion no valida\n");break;
                 }
            }while(!( op==4));

        system("pause");
}

int suma (int a, int b)
{
     int result;
     result = a+b;
     return(result);
     }

int resta (int a, int b)
{
     int result;
     result = a-b;
     printf ("El resultado es: %d", result);
     }

int multi (int a, int b)
{
     int result;
     result = a*b;
     printf ("El resultado es: %d", result);
     }