hdu 2544 最短路(图论:迪杰斯特拉||弗洛伊德算法)

#include <cstdio>
#include <iostream>
#include <cstring>
#include <algorithm>
#define MAXN 10010
#define LL long long
#define INF 0x7fffffff
using namespace std;

int n, m;
bool vis[MAXN];
int d[MAXN];
int g[MAXN][MAXN];

void Dijstra(int s) {
int i, j, x, m;
memset(vis, 0, sizeof(vis));
for(i=1; i<=n; ++i)
d[i] = INF;
d[s] = 0;
for(i=0; i<n; ++i) {
m = INF;
for(j=1; j<=n; ++j)
if(!vis[j] && d[j]<m)
m = d[x=j];
vis[x] = true;
for(j=1; j<=n; ++j) {
if(g[x][j]<INF && d[x]<INF)
d[j] = min(d[j], d[x]+g[x][j]);
}
}
}

int main(void) {
int i, j, x, y, w;
while(scanf("%d%d", &n, &m) && n+m) {
for(i=1; i<=n; ++i)
for(j=i; j<=n; ++j)
g[i][j] = g[j][i] = INF;
for(i=0; i<m; ++i) {
scanf("%d%d%d", &x, &y, &w);
g[x][y] = g[y][x] = w;
}
Dijstra(1);
cout << d
<< endl;
}
return 0;
}

#include <cstdio>
#include <iostream>
#include <cstring>
#include <algorithm>
#define MAXN 10010
#define LL long long
#define INF 0x7fffffff
using namespace std;

int n, m;
int g[MAXN][MAXN];

void floyd() {
int i, j, k;
for(k=1; k<=n; ++k)
for(i=1; i<=n; ++i)
for(j=1; j<=n; ++j)
if(g[i][k]<INF && g[k][j]<INF)
g[i][j] = min(g[i][j], g[i][k]+g[k][j]);
}

int main(void) {
int i, j, x, y, w;
while(scanf("%d%d", &n, &m) && n+m) {
for(i=1; i<=n; ++i) {
g[i][i] = 0;
for(j=i+1; j<=n; ++j)
g[i][j] = g[j][i] = INF;
}
for(i=0; i<m; ++i) {
scanf("%d%d%d", &x, &y, &w);
g[x][y] = g[y][x] = w;
}
floyd();
cout << g[1]
<< endl;
}
return 0;
}