[SWEA 1954] 달팽이 숫자

https://swexpertacademy.com/main/code/problem/problemDetail.do?contestProbId=AV5PobmqAPoDFAUq 

SW Expert Academy

#include <cstdio>
#include <cstring>
int T;
int N;
int S[10 + 2][10 + 2];


void draw_snail()
{
	// init
	int num = 1;
	int x = 0; 
	int y = 0;
	int p = 0;
	S[x][y] = num;

	// dir
	int dir_x[4] = { 0, 1, 0, -1 };
	int dir_y[4] = { 1, 0, -1, 0 };


	while (1) {
		if (num == N * N) break;
		int nx = x + dir_x[p];
		int ny = y + dir_y[p];

		if (nx < 0 || nx > N - 1 || ny < 0 || ny > N - 1 || S[nx][ny] != 0) {
			p = (p + 1) % 4;
			continue;
		}
		num++;
		S[nx][ny] = num;
		x = nx; y = ny; 
	}
}

void output(int t)
{
	printf("#%d\n", t);
	for (int i = 0; i < N; i++) { 
		for (int j = 0; j < N; j++) {
			printf("%d ", S[i][j]);
		}
		printf("\n");
	}
}



int main()
{
	scanf("%d", &T);
	for (int t = 1; t <= T; t++) {
		memset(S, 0, sizeof(S));
		scanf("%d", &N);
		draw_snail();
		output(t);
	}
	return 0;
}