입력받은 수만큼 달팽이 배열 출력

#include <stdio.h>
int main() {
    int a, sum=1, arr[25][25], cnt, m;
    int x = -1, y = 0;
    scanf("%d", &a);
    m = a;
    cnt = a / 2;
    while (1) {
        for (int i = 0; i < a; i++) {
            x += 1;
            arr[y][x] = sum++;
        }
        for (int i = 0; i < a - 1; i++) {
            y += 1;
            arr[y][x] = sum++;
        }
        for (int i = 0; i < a - 1; i++) {
            x -= 1;
            arr[y][x] = sum++;
        }
        for (int i = 0; i < a - 2; i++) {
            y -= 1;
            arr[y][x] = sum++;
        }
        a -= 2;
        cnt--; 
        if (cnt == 0) break;
    }
    if (m % 2 == 1)
        arr[m / 2][m / 2] = sum;
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < m; j++) {
            printf("%3d", arr[i][j]);
        }
        printf("\n");
    }
}