HDU2544 最短路 题解 Bellman-Ford算法
题目链接:https://acm.hdu.edu.cn/showproblem.php?pid=2544
题目大意:一道简单的最短路。主要是记录一下 bellman-ford 算法的实现。
示例程序(bellman-ford):
#include <bits/stdc++.h>
using namespace std;
const int maxn = 110, maxm = 20020;
int n, m, dis[maxn]; // , pre[maxn];
struct Edge {
int u, v, w;
} edge[maxm];
int main() {
while (~scanf("%d%d", &n, &m) && n) {
memset(dis, 0x3f, sizeof(int)*(n+1));
// memset(pre, 0, sizeof(int)*(n+1));
dis[1] = 0;
for (int i = 0; i < 2*m; i += 2) {
int u, v, w;
scanf("%d%d%d", &u, &v, &w);
edge[i] = {u, v, w};
edge[i+1] = {v, u, w};
}
m *= 2;
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) {
int u = edge[j].u, v = edge[j].v, w = edge[j].w;
if (dis[v] > dis[u] + w) {
dis[v] = dis[u] + w;
// pre[v] = u;
}
}
}
printf("%d\n", dis[n]);
}
return 0;
}