A8code/A8code.c

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>

#define N 3  // <20><><EFBFBD><EFBFBD>ƴͼ<C6B4><CDBC>ά<EFBFBD>ȣ<EFBFBD><C8A3><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><D2BB>3x3<78><33>ƴͼ

typedef struct Node {
    int puzzle[N][N];  // <20>洢ƴͼ״̬<D7B4><CCAC><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    struct Node* parent;  // ָ<>򸸽ڵ<F2B8B8BD><DAB5><EFBFBD>ָ<EFBFBD>룬<EFBFBD><EBA3AC><EFBFBD><EFBFBD>׷<EFBFBD><D7B7>·<EFBFBD><C2B7>
    int f, g, h;  // A*<2A>㷨<EFBFBD>е<EFBFBD> f, g, h ֵ
} Node;

// <20><><EFBFBD><EFBFBD><EFBFBD>µ<EFBFBD>ƴͼ<C6B4>ڵ<EFBFBD>
Node* createNode(int puzzle[N][N]) {
    Node* newnode = (Node*)malloc(sizeof(Node));
    //<2F><>ʵ<EFBFBD>ָú<D6B8><C3BA><EFBFBD>
    for (int i = 0; i < N; i++)
    {
        for (int j = 0; j < N; j++)
        {
            newnode->puzzle[i][j] = puzzle[i][j];
        }
    }
    newnode->parent = NULL;
    newnode->f = 0;
    newnode->g = 0;
    newnode->h = 0;
    return newnode;
}

// <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƴͼ״̬<D7B4>Ƿ<EFBFBD><C7B7><EFBFBD>ͬ
bool isSamePuzzle(int a[N][N], int b[N][N]) {
    //<2F><>ͬ<EFBFBD>򷵻<EFBFBD>true,<2C><><EFBFBD>򷵻<EFBFBD>false
    for (int i = 0; i < N; i++)
    {
        for (int j = 0; j < N; j++)
        {
            if (a[i][j] != b[i][j])
            {
                return false;
            }
        }
    }
    return true;
}

// <20><>ӡƴͼ״̬
void printPuzzle(int puzzle[N][N]) {
    //˫<><CBAB>forѭ<72><D1AD>ʵ<EFBFBD><CAB5>ƴͼ<C6B4>Ĵ<EFBFBD>ӡ
    for (int i = 0; i < N; i++)
    {
        for (int j = 0; j < N; j++)
        {
            printf("%d ", puzzle[i][j]);
        }
        printf("\n");
    }
    printf("\n");
}


// <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>㵱ǰ״̬<D7B4><CCAC>Ŀ<EFBFBD><C4BF>״̬<D7B4>Ĺ<EFBFBD><C4B9>ƴ<EFBFBD><C6B4><EFBFBD>
int heuristic(Node* current, Node* goal) { 
    int h = 0;
    // <20><><EFBFBD>㲻ƥ<E3B2BB><C6A5><EFBFBD><EFBFBD>ƴͼ<C6B4><CDBC><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
    for (int i = 0; i < N; i++)
    {
        for (int j = 0; j < N; j++)
        {
            if (current->puzzle[i][j] != goal->puzzle[i][j])
            {
                h++;
            }
        }
    }
    return h;
}

// <20>ƶ<EFBFBD><C6B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>µ<EFBFBD>ƴͼ״̬
Node* move(Node* current, int dir) {
    int key_x, key_y;//<2F><>¼<EFBFBD>հ׿<D5B0><D7BF><EFBFBD>λ<EFBFBD><CEBB>
    // <20>ҵ<EFBFBD><D2B5>հ׿<D5B0><D7BF><EFBFBD>λ<EFBFBD><CEBB>
    for (int i = 0; i < N; i++)
    {
        for (int j = 0; j < N; j++)
        {
            if (current->puzzle[i][j] == 0)
            {
                key_x = i;
                key_y = j;
                break;
            }
        }
    }
    //<2F><>new_x<5F><78>new_y<5F><79>ֵ
    int new_x = key_x, new_y = key_y;
    // <20><><EFBFBD><EFBFBD><EFBFBD>ƶ<EFBFBD><C6B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>¿<EFBFBD><C2BF><EFBFBD>λ<EFBFBD>ã<EFBFBD><C3A3><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƶ<EFBFBD>
    if (dir == 0)
    {
        new_x--;
    }
    else if (dir == 1)
    {
        new_x++;
    }
    else if (dir == 2)
    {
        new_y--;
    }
    else
    {
        new_y++;
    }
    // <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>λ<EFBFBD><CEBB><EFBFBD>Ƿ<EFBFBD><C7B7>ڱ߽<DAB1><DFBD><EFBFBD>
    if (new_x < 0 || new_x >= N || new_y < 0 || new_y >= N)
    {
        return NULL;
    }
    // <20><><EFBFBD><EFBFBD><EFBFBD>½ڵ㣬<DAB5><E3A3AC><EFBFBD>Ƶ<EFBFBD>ǰƴͼ״̬<D7B4><CCAC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>λ<EFBFBD><CEBB>
    Node* new_node = createNode(current->puzzle);
    new_node->puzzle[key_x][key_y] = current->puzzle[new_x][new_y];
    new_node->puzzle[new_x][new_y] = 0;
    return new_node;
}

// A*<2A>㷨<EFBFBD><E3B7A8>Ѱ<EFBFBD><D1B0><EFBFBD><EFBFBD><EFBFBD><EFBFBD>·<EFBFBD><C2B7>
Node* AStar(Node* start, Node* goal) {
    Node* OPEN[1000];  // <20><><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڴ洢<DAB4><E6B4A2>̽<EFBFBD><CCBD><EFBFBD>Ľڵ<C4BD>
    Node* CLOSED[1000];  // <20>ر<EFBFBD><D8B1>б<EFBFBD><D0B1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڴ洢<DAB4><E6B4A2>̽<EFBFBD><CCBD><EFBFBD>Ľڵ<C4BD>
    int OPEN_SIZE = 0;  // <20><><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1>Ĵ<EFBFBD>С
    int CLOSED_SIZE = 0;  // <20>ر<EFBFBD><D8B1>б<EFBFBD><D0B1>Ĵ<EFBFBD>С

    OPEN[0] = start;  // <20><><EFBFBD><EFBFBD>ʼ<EFBFBD>ڵ<EFBFBD><DAB5><EFBFBD><EFBFBD>ӵ<EFBFBD><D3B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD>
    OPEN_SIZE = 1;  // <20><><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1>Ĵ<EFBFBD>С<EFBFBD><D0A1><EFBFBD><EFBFBD>Ϊ1
    CLOSED_SIZE = 0;  // <20>ر<EFBFBD><D8B1>б<EFBFBD><D0B1>Ĵ<EFBFBD>С<EFBFBD><D0A1><EFBFBD><EFBFBD>Ϊ0

    while (OPEN_SIZE > 0) {//<2F><>open<65>б<EFBFBD><D0B1><EFBFBD><EFBFBD>в<EFBFBD><D0B2><EFBFBD>
        int min_f = OPEN[0]->f;//<2F><>ʼ<EFBFBD><CABC><EFBFBD><EFBFBD>С<EFBFBD><D0A1>f
        int min_index = 0;
        // <20><><EFBFBD>ҿ<EFBFBD><D2BF><EFBFBD><EFBFBD>б<EFBFBD><D0B1>о<EFBFBD><D0BE><EFBFBD><EFBFBD><EFBFBD>Сfֵ<66>Ľڵ<C4BD>
        for (int i = 0; i < OPEN_SIZE; i++)
        {
            if (min_f > OPEN[i]->f)
            {
                min_f = OPEN[i]->f;
                min_index = i;
            }
        }
        
        Node* current = OPEN[min_index];  // <20><>ȡ<EFBFBD><C8A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Сfֵ<66>Ľڵ<C4BD>

        // <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǰ<EFBFBD>ڵ<EFBFBD><DAB5><EFBFBD>Ŀ<EFBFBD><C4BF>״̬ƥ<CCAC>䣬<EFBFBD><E4A3AC>ʾ<EFBFBD>ҵ<EFBFBD><D2B5><EFBFBD>
        if (isSamePuzzle(current, goal))
        {
            return current;
        }

        //<2F><><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1>Ĵ<EFBFBD>С<EFBFBD><D0A1>1<EFBFBD><31><EFBFBD><EFBFBD>ʾ<EFBFBD>ӿ<EFBFBD><D3BF><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD><EFBFBD>Ƴ<EFBFBD><C6B3><EFBFBD>һ<EFBFBD><D2BB><EFBFBD>ڵ<EFBFBD>
        OPEN_SIZE--;  

        //<2F><><EFBFBD><EFBFBD>С f ֵ<>Ľڵ<C4BD><DAB5>Ƶ<EFBFBD><C6B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD>ĩβ<C4A9><CEB2><EFBFBD>Ա<EFBFBD><D4B1>Ժ<EFBFBD><D4BA><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӵ<EFBFBD><D3B5>ر<EFBFBD><D8B1>б<EFBFBD><D0B1>С<EFBFBD>
        //<2F><><EFBFBD><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD>Ż<EFBFBD><C5BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1>Ľṹ<C4BD><E1B9B9>
        Node* temp = OPEN[min_index];
        OPEN[min_index] = OPEN[OPEN_SIZE];
        OPEN[OPEN_SIZE] = temp;

        //<2F><><EFBFBD><EFBFBD>ǰ<EFBFBD>ڵ<EFBFBD><DAB5><EFBFBD><EFBFBD>ӵ<EFBFBD><D3B5>ر<EFBFBD><D8B1>б<EFBFBD><D0B1><EFBFBD><EFBFBD>ر<EFBFBD><D8B1>б<EFBFBD><D0B1><EFBFBD>С<EFBFBD><D0A1>1
        CLOSED[CLOSED_SIZE] = current;
        CLOSED_SIZE++;
        int key = 0;
        // <20><><EFBFBD>ҵ<EFBFBD>ǰ<EFBFBD>ڵ<EFBFBD><DAB5>пհ׿<D5B0><D7BF><EFBFBD>λ<EFBFBD><CEBB>
        for (int i = 0; i < N; i++) {
            for (int j = 0; j < N; j++) {
                if (current->puzzle[i][j] == 0) {
                    key = i * N + j;
                    break;
                }
            }
        }

        // <20><><EFBFBD><EFBFBD><EFBFBD>ĸ<EFBFBD><C4B8><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƶ<EFBFBD><C6B6><EFBFBD><EFBFBD><EFBFBD>
        for (int dir = 0; dir < 4; dir++) {
            Node* new_node = move(current, dir);

            if (new_node != NULL && !isSamePuzzle(new_node->puzzle, current->puzzle)) {
                //<2F>õ<EFBFBD><C3B5><EFBFBD>Ӧ<EFBFBD><D3A6>g<EFBFBD><67>f<EFBFBD><66>hֵ
                int gNew = current->g + 1;
                int hNew = heuristic(new_node, goal);
                int fNew = gNew + hNew;

                bool in_OPEN = false;
                int open_index = -1;
                // <20><><EFBFBD><EFBFBD><EFBFBD>½ڵ<C2BD><DAB5>Ƿ<EFBFBD><C7B7>ڿ<EFBFBD><DABF><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD>
                for (int i = 0; i < OPEN_SIZE; i++) {
                    if (isSamePuzzle(new_node->puzzle, OPEN[i]->puzzle)) {
                        in_OPEN = true;
                        open_index = i;
                        break;
                    }
                }

                bool in_CLOSED = false;

                // <20><><EFBFBD><EFBFBD><EFBFBD>½ڵ<C2BD><DAB5>Ƿ<EFBFBD><C7B7>ڹر<DAB9><D8B1>б<EFBFBD><D0B1><EFBFBD>
                for (int i = 0; i < CLOSED_SIZE; i++) {
                    if (isSamePuzzle(new_node->puzzle, CLOSED[i]->puzzle)) {
                        in_CLOSED = true;
                        break;
                    }
                }
                //<2F><><EFBFBD>ýڵ<C3BD><DAB5><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ڿ<EFBFBD><DABF><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD>Ҳ<EFBFBD><D2B2><EFBFBD>ڹر<DAB9><D8B1>б<EFBFBD><D0B1><EFBFBD>
                if (!in_OPEN && !in_CLOSED) {
                    //<2F><>gNew<65><77>hNew<65><77>fNew<65><77><EFBFBD><EFBFBD>new_nod<6F><64>Ӧ<EFBFBD><D3A6>g<EFBFBD><67>h<EFBFBD><68>fֵ<66><D6B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>丸<EFBFBD>ڵ<EFBFBD><DAB5><EFBFBD><EFBFBD><EFBFBD>Ϊ<EFBFBD><CEAA>ǰ<EFBFBD>ڵ㡣
                    new_node->g = gNew;
                    new_node->h = hNew;
                    new_node->f = fNew;
                    new_node->parent = current;
                    // <20><><EFBFBD><EFBFBD><EFBFBD>½ڵ<C2BD>new_node<64><65><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD>С<EFBFBD><D0A1>1
                    OPEN[OPEN_SIZE] = new_node;
                    OPEN_SIZE++;
                } 
                //<2F><><EFBFBD><EFBFBD><EFBFBD>½ڵ<C2BD><DAB5>Ѿ<EFBFBD><D1BE>ڿ<EFBFBD><DABF><EFBFBD><EFBFBD>б<EFBFBD><D0B1>У<EFBFBD><D0A3><EFBFBD><EFBFBD>µ<EFBFBD> f ֵ<><D6B5>С<EFBFBD><D0A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>¿<EFBFBD><C2BF><EFBFBD><EFBFBD>б<EFBFBD><D0B1><EFBFBD><EFBFBD>Ѵ<EFBFBD><D1B4>ڽڵ<DABD><DAB5><EFBFBD><EFBFBD><EFBFBD>Ϣ<EFBFBD><CFA2>
                else if (in_OPEN && fNew < OPEN[open_index]->f) {
                    OPEN[open_index] = new_node;
                }
            }
        }
    }

    return NULL;  // <20>޽<EFBFBD>
}

// <20><>ӡ<EFBFBD><D3A1>·<EFBFBD><C2B7>
void printPath(Node* final) {
    if (final == NULL) {
        return;
    }
    printPath(final->parent);  // <20>ݹ<EFBFBD><DDB9><EFBFBD>ӡ·<D3A1><C2B7>
    for (int i = 0; i < N; i++) {
        if (i%3==0){
            printf("-------\n");
        }
        for (int j = 0; j < N; j++) {
            printf("%d ", final->puzzle[i][j]);
        }
        
        printf("\n");
        
    }
}

int main() {
    //int start[N][N] = {{2, 0, 3}, {1, 8, 4}, {7, 6, 5}};
    //int target[N][N] = {{1, 2, 3}, {8, 0, 4}, {7, 6, 5}};

    // int start[N][N] = {{2, 8, 3}, {1, 6, 4}, {7, 0, 5}};
    // int target[N][N] = {{1, 2, 3}, {8, 0, 4}, {7, 6, 5}};

    int start[N][N] = {{2, 8, 3}, {1, 0, 4}, {7, 6, 5}};
    int target[N][N] = {{1, 2, 3}, {8, 0, 4}, {7, 6, 5}};
    Node* init = createNode(start);
    Node* goal = createNode(target);

    Node* final = AStar(init, goal);
    if (final) {
        printf("This problem has a solution:\n");
        printPath(final);  // <20><>ӡ<EFBFBD><D3A1>·<EFBFBD><C2B7>
    } else {
        printf("This problem has no solution<6F><6E>\n");
    }

    return 0;
}