DFS路径规划

#include <stdio.h>
#include <iostream>

int width = 6;
int height = 5;
int map[5][6] = { {0,0,0,0,0,0},
                           {1,0,0,1,0,1},
                           {0,0,1,0,0,0},
                           {1,0,0,1,0,1},
                           {0,1,0,0,0,0} };

int path[20] = { 0 }; //0--stop,1--forward,2--left,3--right,4--back 

int find_path(int x, int y, int flag,   //x,y为在map中的位置，flag代表之前走的方向(0--上，1--下，2--左，3--右)，
    int x_,                  //x代表path的下标 
    int target_x, int target_y)  //target_x,target_y代表要找到的具体位置 
{
    map[x][y] = 1;
    int temp;
    int flag_ = flag;
    int x__ = x_;
    if (x == target_x && y == target_y)
    {
        return x_;
    }

    if (flag == 0) {
        if (x > 0) {
            if (map[x - 1][y] == 0) {
                path[x_] = 1; 
                temp = find_path(x - 1, y, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x - 1][y] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }

        if (y < width-1 ) {
            if (map[x][y + 1] == 0) {
                path[x_] = 3;
                path[++x_] = 1; 
                //if (flag == 2) { path[x_] = 4; }
                flag = 3;
                temp = find_path(x, y + 1, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x][y + 1] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else { return temp; }
            }
        }

        if (y > 0) {
            if (map[x][y - 1] == 0) {
                path[x_] = 2;
                path[++x_] = 1;
                flag = 2;
                temp = find_path(x, y - 1, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x][y - 1] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }
    }


    if (flag == 1) {
        if (x < height - 1) {
            if (map[x + 1][y] == 0) {
                 path[x_] = 1; 
                temp = find_path(x + 1, y, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x + 1][y] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }

        if (y < width - 1) {
            if (map[x][y + 1] == 0) {
                path[x_] = 2;
                path[++x_] = 1;
                flag = 3;
                temp = find_path(x, y + 1, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x][y + 1] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else { return temp; }
            }
        }

        if (y > 0) {
            if (map[x][y - 1] == 0) {
                path[x_] = 3;
                path[++x_] = 1;
                flag = 2;
                temp = find_path(x, y - 1, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x][y - 1] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }
    }

    if (flag == 2) {
        if (y > 0) {
            if (map[x][y - 1] == 0) {
                path[x_] = 1; 
                temp = find_path(x, y - 1, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x][y - 1] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }

        if (x > 0) {
            if (map[x - 1][y] == 0) {
                path[x_] = 3;
                path[++x_] = 1;
                flag = 0;
                temp = find_path(x - 1, y, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x - 1][y] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }

        if (x < height - 1) {
            if (map[x + 1][y] == 0) {
                path[x_] = 2; 
                path[++x_] = 1; 
                flag = 1;
                temp = find_path(x + 1, y, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x + 1][y] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }
    }

    if (flag == 3) {

        if (y < width - 1) {
            if (map[x][y + 1] == 0) {
                path[x_] = 1;
                temp = find_path(x, y + 1, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x][y + 1] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else { return temp; }
            }
        }

        if (x > 0) {
            if (map[x - 1][y] == 0) {
                path[x_] = 2;
                path[++x_] = 1;
                flag = 0;
                temp = find_path(x - 1, y, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x - 1][y] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }

        if (x < height - 1) {
            if (map[x + 1][y] == 0) {
                path[x_] = 3;
                path[++x_] = 1; 
                flag = 1;
                temp = find_path(x + 1, y, flag, x_ + 1, target_x, target_y);
                if (temp == 0) {
                    map[x + 1][y] = 1;
                    flag = flag_;
                    x_ = x__;
                }
                else {
                    return temp;
                }
            }
        }
    }
    //map[x][y] = 0;
    return 0;
}

int main() {
    int x, y, x_, y_;
    int flag;
    for (int i = 0; i < 5; i++) {
        for (int j = 0; j < 6; j++) {
            printf_s("%d ", map[i][j]);
        }
        printf_s("
");
    }
    printf_s("请输入您的起点: ");
    scanf_s("%d%d", &x, &y);
    printf_s("请输入您的终点：");
    scanf_s("%d%d", &x_, &y_);
    printf_s("请输入默认的初始方向（0 -- 上，1 -- 下，2 -- 左，3 -- 右）");
    scanf_s("%d", &flag);
    x = find_path(x, y, flag, 0, x_, y_);
    for (int i = 0; i < x; i++) {
        if (path[i] == 0) break;
        if (path[i] == 1) printf_s("forward
");
        if (path[i] == 2) printf_s("left
");
        if (path[i] == 3) printf_s("right
");
    }
    system("pause");
    return 0;
}