Thread: This should be so simple!!!

I've created this program and I'm trying to run in codeblocks 8.02 but it doesn't get further than the intial user input.

The program should use a menu system to run funtions which double, square or cube their input number.

Any ideas???

Code:

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

int doublenum(int userin);
int square(int userin);
int cube(int userin);

int main(void)
{
    int menuchoice = 0, userin, out;

    printf("\nEnter a number: ");
    scanf("%d", &userin);

    while(menuchoice != 4);
        {
            printf("\n1\tDouble\n2\tSquare\n3\tCube4\tQuit\n\nPlease choose an option: ");
            scanf("%d", &menuchoice);

            switch (menuchoice) {
                case 1: out = doublenum(userin);
                        printf("\n%d", out);
                    break;
                case 2: out = square(userin);
                        printf("\n%d", out);
                    break;
                case 3: out = cube(userin);
                        printf("\n%d", out);
                    break;
                default: printf("\nMENU CHOICE ERROR!\n");
                    break;
            }
        }
    return 0;
}

int doublenum(int userin)
{
    return userin + userin;
}

int square(int userin)
{
    return userin * userin;
}

int cube(int userin)
{
    return userin * userin * userin;
}