leetcode刷题 二维数组 八方向

题目描述

输入：board = [[0,1,0],[0,0,1],[1,1,1],[0,0,0]]
输出：[[0,0,0],[1,0,1],[0,1,1],[0,1,0]]

题目分析:就是以二维数组某个元素为中心，寻找周围八个方向的元素，按照题目要求修改二维数组元素返回；
拷贝一份二维数组；

参数分析
void gameOfLife(int** board, int boardSize, int* boardColSize)

**board定义了一个指向整型变量指针的指针，就是二维数组的首地址
boardSize表示行； 4
boardColSize 表示列，每行有多少列 ；== 3

#define DIRECTION_NUM 8
#define DIRECTION_SIZE 2
int directions[DIRECTION_NUM][DIRECTION_SIZE] = {{0, 1}, {1, 0}, {0, -1}, {-1, 0}, {1, 1}, {1, -1}, {-1, 1}, {-1, -1}};

int JudgeLive(int **copyBoard, int rowSize, int colSize, int x, int y)
{
    int result = 0;
    for (int i = 0; i < DIRECTION_NUM; i++) {
        int tempX = x + directions[i][0];//每次按这个方向做偏移
        int tempY = y + directions[i][1];
        if (tempX < 0 || tempX >= rowSize || tempY < 0 || tempY >= colSize) {
            continue;
        } else {
            result += copyBoard[tempX][tempY];
        }
    }
    return result;
}

void gameOfLife(int** board, int boardSize, int* boardColSize){
    //外面大的申请一次
    int **copyBoard = (int **)malloc(sizeof(int *) * boardSize);
    //循环申请空间
    for (int i = 0; i < boardSize; i++) {
        copyBoard[i] = (int *)malloc(sizeof(int) * (*boardColSize));
    }
    //给copy的数组赋值
    for (int i= 0; i < boardSize; i++) {
        for (int j = 0; j < *boardColSize; j++) {
            copyBoard[i][j] = board[i][j];
        }
    }
    for (int i= 0; i < boardSize; i++) {
        for (int j = 0; j < *boardColSize; j++) {
            int result = JudgeLive(copyBoard, boardSize, *boardColSize, i, j);
            if (board[i][j] == 0 && result == 3) {
                board[i][j] = 1;
            }
            if (board[i][j] == 1 && (result < 2 || result > 3)) {
                board[i][j] = 0;
            }
        }
    }
}