Thread: How to make a program with multiple functions run with main function at the top?

So basically I was working on my homework, basically completed everything, but one trick was to make the program have no warnings even with the int main(void) at the top of the program.
I literally researched and tried almost everything but could not get it to work. Im stumped and I need yalls help!

When I run it, it works perfectly, but showed warnings when I compiled it.

I purposely left out code in functions to not be a victim, if you need more, let me know.

TLDR: I need to make this run with no warnings.

Code:

int main(void){
        int max = 100;
        int randnums[max];
        populateArray(randnums,max);

        insertionSort(randnums,max);
        printArray(randnums, max);

}

void populateArray(int* randnums, int max){
        

}
void insertionSort(int * randnums,int max){
        swap(val1,val2);
}

void swap(int* val1, int* val2){
        
}

void printArray(int* randnums,int  max) {
        
}