Improved Tic Tac Toe

#include <stdio.h>  // Tic-Tac-Toe (Random Moves)
#include <stdlib.h> // Code by: The Elite Noob
#include <time.h>

int clean();
void display(int* ar);
void getinput(int(*validity)(int* ar, int l), int* ar); // (int l is location)
int checkwin(int* ar);
int validmove(int* ar, int place);
void aimove(int(*validity)(int* ar, int l), int* ar);

int main (int argc, char *argv[]){
    int board[] = {32, 32, 32, 32, 32, 32, 32, 32, 32}; // The board (ascii values), 32 is blank, 111 is o, and 120 is x(player);
    display(board);
    while(checkwin(board) == -1){
        getinput(validmove, board);
        display(board);
        if(checkwin(board) != -1)
            break;
        aimove(validmove, board);
        display(board);
        if(checkwin(board) != -1)
            break;
    }
    printf("%c wins!\n", checkwin(board));
    return 0;
}

void aimove(int(*validity)(int* ar, int l), int* ar){
    int r;
    srand(time(NULL));
    do{
        r = (rand() % 10) + 1;  // Random num from 1 to 9
    }while((*validity)(ar, r) == -1); // Check if move is valid (Yay function pointers)
    ar[r-1] = 111; // AI move..
}

void getinput(int(*validity)(int* ar, int l), int* ar){ // Get and sanatize input
    char c; // First get the input, then make sure it's a valid move... c is used for garbage stuff
    int input;
    do{
        printf("\nEnter move: ");
    }while(!(((scanf("%d%c", &input, &c)!=2 || c!='\n') && clean()) ||input<1 || input>9) && ((*validity)(ar, input) == -1)); // Magic.
    ar[input-1] = 120; // Place/actually set the board piece
}

int validmove(int* ar, int place){ // If move is not valid, return -1
    if((ar[place-1] == 111)||(ar[place-1] == 120)){
        printf("\nInvalid move.");
        return -1;
    }
    return 1;
}

void display(int* ar){ // Display the board
    int i; // Iterator
    printf("\n");
    for (i = 0; i < 7; i+=3){
        printf("%c | %c | %c\n", ar[i], ar[i+1], ar[i+2]);
        if(i < 4)
            printf("----------\n");
    }
}

int checkwin(int* ar){ // Check if we have any winner yet..
    int i; // Iterator
    for(i = 0; i < 7; i+=3) // Check rows
        if((ar[i] == ar[i+1]) && (ar[i] == ar[i+2]) && (ar[i] != 32))
            return ar[i];
    for(i = 0; i < 3; i++)  // Check cols
        if((ar[i] == ar[i+3]) && (ar[i] == ar[i+6]) && (ar[i] != 32))
            return ar[i];
    if((ar[0] == ar[4]) && (ar[0] == ar[8]) && (ar[0] != 32))   // Check diags
        return ar[0];
    if((ar[2] == ar[4]) && (ar[2] == ar[6]) && (ar[2] != 32))   // Check diags
        return ar[2];
    return -1; // No winner yet.
}

int clean(){ // Flushes input
    while (getchar()!='\n');
    return 1;
}