顺时针打印个数组_First Snowflakes的博客-CSDN博客

顺时针打印个N*N数组：

code:

Just like state machine.

#include <thread>
#include <mutex>
#include <list>
#include <cstdlib>
#include <iomanip>
#include <iostream>
#include <vector>
using namespace std;

enum Dir {
    right = 0,
    left,
    down,
    up
};
Dir getNextDirection(const int rowIdx, const int colIdx, const int N, \
                     Dir currDir, \
                     vector<vector<bool>>& filled) {
    if (currDir == Dir::right) {
        if ((colIdx + 1) < N && (!filled[rowIdx][colIdx + 1])) {
            return Dir::right;
        }
        else {
            return Dir::down;
        }
    }else if (currDir == Dir::left) {
        if ((colIdx - 1) >= 0 && (!filled[rowIdx][colIdx - 1])) {
            return Dir::left;
        }
        else {
            return Dir::up;
        }
    }else if (currDir == Dir::up) {
        if ((rowIdx - 1) >= 0 && (!filled[rowIdx-1][colIdx])) {
            return Dir::up;
        }
        else {
            return Dir::right;
        }
    } else if (currDir == Dir::down) {
        if ((rowIdx + 1) < N && (!filled[rowIdx + 1][colIdx])) {
            return Dir::down;
        }
        else {
            return Dir::left;
        }
    }
}

void func(int N) {
    if (N < 1) {
        return;
    }
    const int totalNum = N * N;
    vector<vector<bool>> filled(N, vector<bool>(N,false));
    vector<vector<int>> result(N, vector<int>(N, 0));
    Dir currDir = Dir::right;
    int currRowIdx = 0;
    int currColIdx = 0;
    result[currRowIdx][currColIdx] = 0;
    filled[currRowIdx][currColIdx] = true;
    for (int i = 1; i < totalNum; ++i) {
        currDir = getNextDirection(currRowIdx, currColIdx, N, currDir, filled);
        if (currDir == Dir::right) {
            currColIdx++;
        } else if (currDir == Dir::left) {
            currColIdx--;
        }if (currDir == Dir::up) {
            currRowIdx--;
        }if (currDir == Dir::down) {
            currRowIdx++;
        }
        result[currRowIdx][currColIdx] = i;
        filled[currRowIdx][currColIdx] = true;
        if (i == (totalNum - 1)) {
            break;
        }
    }
    // print:
    std::cout << std::endl;
    for (auto& arr : result) {
        for (auto& val : arr) {
            std::cout << std::setw(5) << val << "  ";
        }
        std::cout << std::endl;
    }
}
int main() {
    func(5);
    return 0;
}