螺旋矩阵

coding>C++
976 词

题目描述

给定一个正整数n$(1<=n<=20)$，画出螺旋矩阵。

输入

一个正整数n

输出

对应画出螺旋矩阵

样例输入

1
5

样例输出

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2
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5
1 2 3 4 5 
16 17 18 19 6 
15 24 25 20 7 
14 23 22 21 8 
13 12 11 10 9

提示

每一个数后输出空格

题解

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#include <iostream>
using namespace std;
int a[21][21];
int n;
int main() {
    cin >> n;
    int x = 0, y = 0;
    a[x][y] = 1;
    for (int k = 2; k <= n * n; ) {
        while (true) {
            int nx = x, ny = y + 1;
            if (nx < 0  nx >= n  ny < 0  ny >= n  a[nx][ny]) {
                break;
            }
            a[x = nx][y = ny] = k++;
        }
        while (true) {
            int nx = x + 1, ny = y;
            if (nx < 0  nx >= n  ny < 0  ny >= n  a[nx][ny]) {
                break;
            }
            a[x = nx][y = ny] = k++;
        }
        while (true) {
            int nx = x, ny = y - 1;
            if (nx < 0  nx >= n  ny < 0  ny >= n  a[nx][ny]) {
                break;
            }
            a[x = nx][y = ny] = k++;
        }
        while (true) {
            int nx = x - 1, ny = y;
            if (nx < 0  nx >= n  ny < 0  ny >= n  a[nx][ny]) {
                break;
            }
            a[x = nx][y = ny] = k++;
        }
    }
    for (int ii = 0; ii < n; ii++) {
        for (int  jj = 0; jj < n; jj++) {
            cout << a[ii][jj] << " ";
        }
        cout << endl;
    }
    return 0;
}