Floyd(最短路径问题）
[cpp]#include <iostream>
#include <cstdio>
#include <cstring>
#define INF 0x7ffffff//如果设为0x7fffffff在执行算法时溢出。
#define maxn 100
using namespace std;
int n;
int edge[maxn][maxn];
int a[maxn][maxn], path[maxn][maxn];
void floyd() {
int i, j, k;
for( i = 0; i < n; i++ ) {
for( j = 0; j < n; j++) {
a[i][j] = edge[i][j];
if( i != j && a[i][j] < INF ) { path[i][j] = i; }
else { path[i][j] = -1; }
}
}
for( k = 0; k < n; k++ ) {
for( i = 0; i < n; i++ ) {
for( j = 0; j < n; j++ ) {
if( k == i || k == j ) { continue; }
if( a[i][k] + a[k][j] < a[i][j] ) {
a[i][j] = a[i][k] + a[k][j];
path[i][j] = path[k][j];
}
}
}
}
}
void output() {
int i, j;
int shortest[maxn];
for( i = 0; i < n; i++ ) {
for( j = 0; j < n; j++ ) {
if( i == j) { continue; }
printf( "%d->%d\t%d\t", i, j, a[i][j] );
memset( shortest, 0, sizeof(shortest) );
int k = 0;
shortest[k] = j;
while( path[i][shortest[k]] != i) {
k++; shortest[k] = path[i][shortest[k-1]];
}
k++; shortest[k] = i;
for( int t = k; t >0; t-- ) {
printf( "%d->", shortest[t] );
}
printf( "%d\n",shortest[0] );
}
}
return;
}
void init() {
int i, j;
int u, v, w;
scanf("%d", &n);
for( i = 0; i < n; i++ ) {
for( j = 0; j < n; j++ ) {
if(i != j) { edge[i][j] = INF; }
else { edge[i][j] = 0; }
}
}
while( 1 ) {
scanf("%d%d%d", &u, &v, &w);
if( u == -1 && v == -1 && w == -1 ) { break; }
edge[u][v] = w;
}
}
int main()
{
init();
floyd();
output();
return 0;
}
/**************************
测试数据：
4
0 1 1
0 3 4
1 2 9
1 3 2
2 0 3
2 1 5
2 3 8
3 2 6
-1 -1 -1
***********************/
补充：软件开发 , C++ ,
