1、Prim算法和Kruskal算法实现最小生成树。C语言

以下是Prim算法和Kruskal算法实现最小生成树的C语言代码：

1. Prim算法实现最小生成树

#include <stdio.h>
#include <limits.h>

#define V 5 // 顶点数

int minKey(int key[], bool mstSet[]) {
    int min = INT_MAX, min_index;
    for (int v = 0; v < V; v++) {
        if (mstSet[v] == false && key[v] < min) {
            min = key[v], min_index = v;
        }
    }
    return min_index;
}

void printMST(int parent[], int graph[V][V]) {
    printf("Edge \tWeight\n");
    for (int i = 1; i < V; i++) {
        printf("%d - %d \t%d \n", parent[i], i, graph[i][parent[i]]);
    }
}

void primMST(int graph[V][V]) {
    int parent[V];
    int key[V];
    bool mstSet[V];
    for (int i = 0; i < V; i++) {
        key[i] = INT_MAX, mstSet[i] = false;
    }
    key[0] = 0;
    parent[0] = -1;
    for (int count = 0; count < V - 1; count++) {
        int u = minKey(key, mstSet);
        mstSet[u] = true;
        for (int v = 0; v < V; v++) {
            if (graph[u][v] && mstSet[v] == false && graph[u][v] < key[v]) {
                parent[v] = u, key[v] = graph[u][v];
            }
        }
    }
    printMST(parent, graph);
}

2. Kruskal算法实现最小生成树

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

#define V 5 // 顶点数
#define E 7 // 边数

struct Edge {
    int src, dest, weight;
};

struct Graph {
    int V, E;
    struct Edge* edge;};

struct Graph* createGraph(int V, int E) {
    struct Graph* graph = (struct Graph*)malloc(sizeof(struct Graph));
    graph->V = V;
    graph->E = E;
    graph->edge = (struct Edge*)malloc(graph->E * sizeof(struct Edge));
    return graph;
}

int find(int parent[], int i) {
    if (parent[i] == -1) {
        return i;
    }
    return find(parent, parent[i]);
}

void Union(int parent[], int x, int y) {
    int xset = find(parent, x);
    int yset = find(parent, y);
    parent[xset] = yset;
}

int myComp(const void* a, const void* b) {
    struct Edge* a1 = (struct Edge*)a;
    struct Edge* b1 = (struct Edge*)b;
    return a1->weight > b1->weight;
}

void KruskalMST(struct Graph* graph) {
    int* parent = (int*)malloc(graph->V * sizeof(int));
    memset(parent, -1, sizeof(int) * graph->V);
    qsort(graph->edge, graph->E, sizeof(graph->edge[0]), myComp);
    struct Edge result[graph->V];
    int e = 0, i = 0;
    while (e < graph->V - 1 && i < graph->E) {
        struct Edge next_edge = graph->edge[i++];
        int x = find(parent, next_edge.src);
        int y = find(parent, next_edge.dest);
        if (x != y) {
            result[e++] = next_edge;
            Union(parent, x, y);
        }
    }
    printf("Following are the edges in the constructed MST\n");
    for (i = 0; i < e; ++i) {
        printf("%d -- %d == %d\n", result[i].src, result[i].dest, result[i].weight);
    }
    return;
}