Data_Structure/作業/unit12/DS7_down.cpp

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

#define MAX_V 100   /*<2A>̤j<CCA4>`<60>I<EFBFBD><49>*/
#define Infinite 1073741823

long int dist[MAX_V+1][MAX_V+1];
int path[MAX_V+1][MAX_V+1];  // <20>l<EFBFBD>ܸ<EFBFBD><DCB8>|<7C><><EFBFBD>x<EFBFBD>}
int N;  // <20>`<60>I<EFBFBD>ƶq
int source, sink;  // <20>_<EFBFBD>I<EFBFBD>M<EFBFBD><4D><EFBFBD>I

void init();
bool floydWarshall();
void output_path();
void output_step();
void print_path(int start, int end);

int main() {
    init();
    
    // <20>ˬd<CBAC>O<EFBFBD>_<EFBFBD>s<EFBFBD>b<EFBFBD>t<EFBFBD>v<EFBFBD>j<EFBFBD><6A>
    if (floydWarshall()) {
        printf("\nĵ<EFBFBD>i<EFBFBD>G<EFBFBD>ϧΤ<EFBFBD><EFBFBD>s<EFBFBD>b<EFBFBD>t<EFBFBD>v<EFBFBD>j<EFBFBD><EFBFBD><EFBFBD>A<EFBFBD>p<EFBFBD>⵲<EFBFBD>G<EFBFBD>i<EFBFBD>ण<EFBFBD><EFBFBD><EFBFBD>T<EFBFBD>I\n");
        output_path();
    } else {
        output_path();
    }
    
    return 0;
}

void init(){
    FILE *fptr;
    int i, j, weight,line_count=0;
    char line[256];

    fptr = fopen("shortestPath_down_1.dat", "r");
    if (fptr == NULL) {
        perror("shortestPath_up_1.dat");
        exit(1);
    }
    
    // <20>p<EFBFBD><70><EFBFBD>`<60><><EFBFBD>I<EFBFBD><49>
    while (fgets(line, sizeof(line), fptr)) {
        line_count++;
    }
    N = line_count;
    rewind(fptr);

        // <20><><EFBFBD>l<EFBFBD>ƶZ<C6B6><5A><EFBFBD>x<EFBFBD>}<7D>P<EFBFBD><50><EFBFBD>|<7C>x<EFBFBD>}
    for (i = 1; i <= N; i++) {
        for (j = 1; j <= N; j++) {
            if (i == j) {
                dist[i][j] = 0;
                path[i][j] = i;
            } else {
                dist[i][j] = Infinite;
                path[i][j] = -1;
            }
        }
    }

    // Ū<><C5AA><EFBFBD>U<EFBFBD>T<EFBFBD><54><EFBFBD>x<EFBFBD>}
    for (i = 1; i <= N; i++) {
        for (j = 1; j < i; j++) {
            if (fscanf(fptr, "%d", &weight) == 1) {
                if (weight != 0) {  // <20>u<EFBFBD>B<EFBFBD>z<EFBFBD>D<EFBFBD>s<EFBFBD>v<EFBFBD><76>
                    dist[i][j] = weight;
                    path[i][j] = i;
                    // <20>]<5D><><EFBFBD>O<EFBFBD>L<EFBFBD>V<EFBFBD>ϡA<CFA1>ҥH<D2A5><48><EFBFBD>٦<EFBFBD><D9A6>m<EFBFBD>]<5D>n<EFBFBD>]<5D>w
                    if (i != j) {
                        dist[j][i] = weight;
                        path[j][i] = j;
                    }
                }
            }
        }
        // <20><><EFBFBD>L<EFBFBD>Ӧ<EFBFBD><D3A6>Ѿl<D1BE><6C><EFBFBD>r<EFBFBD><72>
        fgets(line, sizeof(line), fptr);
    }

    fclose(fptr);
    printf("<EFBFBD>ɮפ<EFBFBD><EFBFBD>v<EFBFBD><EFBFBD><EFBFBD>p<EFBFBD>U\n");
    output_step();
    
    printf("\n<EFBFBD><EFBFBD><EFBFBD>J<EFBFBD>_<EFBFBD>l<EFBFBD>`<60>I (1~%d): ", N);
    scanf("%d", &source);
    printf("<EFBFBD><EFBFBD><EFBFBD>J<EFBFBD>ؼи`<60>I (1~%d): ", N);
    scanf("%d", &sink);
}

bool floydWarshall(){
    int k, i, j;
    bool has_negative_cycle = false;
    long int temp_dist[MAX_V+1][MAX_V+1];

    // <20>D<EFBFBD>n<EFBFBD><6E> Floyd-Warshall <20>t<EFBFBD><74><EFBFBD>k
    for (k = 1; k <= N; k++) {
        for (i = 1; i <= N; i++) {
            for (j = 1; j <= N; j++) {
                if (dist[i][k] != Infinite && 
                    dist[k][j] != Infinite && 
                    dist[i][k] + dist[k][j] < dist[i][j]) {
                    dist[i][j] = dist[i][k] + dist[k][j];
                    path[i][j] = path[k][j];
                }
            }
        }
    }

    // <20>ƻs<C6BB>ثe<D8AB><65><EFBFBD>Z<EFBFBD><5A><EFBFBD>x<EFBFBD>}
    for (i = 1; i <= N; i++) {
        for (j = 1; j <= N; j++) {
            temp_dist[i][j] = dist[i][j];
        }
    }

    // <20>A<EFBFBD><41><EFBFBD><EFBFBD><EFBFBD>@<40><><EFBFBD><EFBFBD><EFBFBD>N<EFBFBD><4E><EFBFBD>ˬd<CBAC>t<EFBFBD>v<EFBFBD>j<EFBFBD><6A>
    for (k = 1; k <= N; k++) {
        for (i = 1; i <= N; i++) {
            for (j = 1; j <= N; j++) {
                if (dist[i][k] != Infinite && 
                    dist[k][j] != Infinite && 
                    dist[i][k] + dist[k][j] < temp_dist[i][j]) {
                    has_negative_cycle = true;
                    goto end_check; // <20><><EFBFBD><EFBFBD><EFBFBD>t<EFBFBD>v<EFBFBD>j<EFBFBD><6A><EFBFBD>᪽<EFBFBD><E1AABD><EFBFBD><EFBFBD><EFBFBD>X
                }
            }
        }
    }

end_check:
    return has_negative_cycle;
}

void print_path(int start, int end) {
    if (start == end) {
        printf("<EFBFBD><EFBFBD><EFBFBD>I%d", start);
        return;
    }
    if (path[start][end] == -1) {
        printf("<EFBFBD>L<EFBFBD><EFBFBD><EFBFBD>|");
        return;
    }
    print_path(start, path[start][end]);
    printf(" <20><> %d", end);
}

void output_step(){
    int i, j;

    printf("\t");
    for (j = 1; j <= N; j++) {
        printf("V%d\t", j);
    }
    printf("\n");

    for (i = 1; i <= N; i++) {
        printf("V%d\t", i);
        for (j = 1; j <= N; j++) {
            if (dist[i][j] == Infinite)
                printf("<EFBFBD><EFBFBD>\t");
            else
                printf("%2ld\t", dist[i][j]);
        }
        printf("\n");
    }
}

void output_path(){
    int i, j;

    printf("\n<EFBFBD>`<60>I<EFBFBD><49><EFBFBD>̵u<CCB5>Z<EFBFBD><5A><EFBFBD>x<EFBFBD>}<7D>G\n");
    output_step();
    
    if (dist[source][sink] == Infinite) {
        printf("\n<EFBFBD>`<60>I V%d <20><><EFBFBD>`<60>I V%d <20>S<EFBFBD><53><EFBFBD><EFBFBD><EFBFBD>|\n", source, sink);
    } else {
        printf("\n<EFBFBD>q<EFBFBD>`<60>I V%d <20><><EFBFBD>`<60>I V%d <20><><EFBFBD>̵u<CCB5>Z<EFBFBD><5A><EFBFBD><EFBFBD><EFBFBD>G%ld\n", 
               source, sink, dist[source][sink]);
        printf("<EFBFBD>̵u<EFBFBD><EFBFBD><EFBFBD>|<7C>G");
        print_path(source, sink);
        printf("\n");
    }
}