數字螺旋方陣

 

#define N 10

#include <stdio.h>
void main() {
	int num[N][N] = {0};
	int i, j, k, r = 1;

	for(i = 0, j = 0; i < N; i++)
		num[i][j] = r++;
	
	for(k = 1; r <= N * N; k++) {
		for(i = N - k, j = k; j <= N - k; j++) 
			num[i][j] = r++;
		for(i = N - k - 1, j = N - k; i >= k - 1; i--)
			num[i][j] = r++;
		for(i = k - 1, j = N - k - 1; j >= k; j--)
			num[i][j] = r++;
		for(i = k, j = k; i <= N - k - 1; i++)
			num[i][j] = r++;
	}
	printf("\n");
	
	/*output*/
	for(i = 0; i < N; i++) {
		for(j = 0; j < N; j++) {
			printf("%5d", num[i][j]);
		}
		printf("\n\n");
	}
	

}