最短路径(Dijikstra和Floyed)

#include <stdio.h>#include <stdlib.h>#include <string.h>#include <limits.h>typedef unsigned int ssize_t;const ssize_t MAXSIZE = 20;static ssize_t  graph  [MAXSIZE][MAXSIZE];static ssize_t  node_num;static char node   [MAXSIZE];#define FLOYED#ifdef DIJIKSTRAstatic ssize_t dist   [MAXSIZE];static char path   [MAXSIZE];static bool visited[MAXSIZE];void find_path_from(char node){ssize_t i = 0, j = 0;ssize_t start_index = node - 'A';ssize_t cur_min_path = 0;char cur_start_index = 0;visited[start_index] = true;for(i = 0; i < node_num - 1; i++){if(graph[start_index][i] < UINT_MAX)dist[i] = graph[start_index][i];elsedist[i] = UINT_MAX;}path[start_index] = 'A' + start_index;dist[start_index] = 0;for(j = 0; j < node_num; j++){cur_min_path = UINT_MAX;for(i = 0; i < node_num; i++){if((visited[i] == false)&& (dist[i] < cur_min_path)){cur_min_path = dist[i];cur_start_index = i;}}visited[cur_start_index] = true;for(i = 0; i < node_num; i++){if((visited[i] == false) &&(dist[i] > dist[cur_start_index] + graph[cur_start_index][i])){dist[i] = dist[cur_start_index] + graph[cur_start_index][i];path[i] = cur_start_index + 'A';}}}}#endif#ifdef FLOYEDvoid floyed(){int k = 0, i = 0, j = 0;for(k = 0; k < node_num; k++){for(i = 0; i < node_num; i++){for(j = 0; j < node_num; j++){if(graph[i][j] > graph[i][k] + graph[k][j])graph[i][j] = graph[i][k] + graph[k][j];}}}}#endifint main(ssize_t argc, char * argv [ ]){ssize_t i = 0, j = 0;ssize_t edge_num = 0;ssize_t distance = 0;char start_node, end_node;#ifdef DIJIKSTRAmemset(graph, 0xFF, MAXSIZE * MAXSIZE * sizeof(ssize_t));memset(dist, 0xFF, MAXSIZE * sizeof(ssize_t));#endifprintf("请输入节点数量(小于%d):", MAXSIZE);scanf("%u", &node_num);for(i = 0; i < node_num; i++)node[i] = 'A' + i;printf("节点编号已自动分配为:%c-%c。\n", 'A', node[node_num - 1]);printf("请输入边的数量:");scanf("%u", &edge_num);while(getchar()!='\n');for(i = 0; i < edge_num; i++){printf("请输入第%d条边(如'A-B:20'):", i + 1 );scanf("%c-%c:%u",&start_node, &end_node, &distance);graph[start_node - 'A'][end_node - 'A'] = distance;graph[end_node - 'A'  ][start_node - 'A'] = distance;while(getchar()!='\n');}#ifdef DIJIKSTRAfind_path_from('A');for(i = 0; i < node_num; i++){printf("%c->%c:%u\n", 'A', node[i], dist[i]);}#endif#ifdef FLOYEDfloyed();for(i = 0; i < node_num; i++){printf("%c->%c:%u\n", 'A', node[i], graph[0][i]);}#endifreturn 0;}