hdu1385 最短路字典序

时间:2023-03-09 19:41:18
hdu1385 最短路字典序

http://blog.****.net/ice_crazy/article/details/7785111

http://blog.****.net/shuangde800/article/details/8075165

http://www.cnblogs.com/qiufeihai/archive/2012/09/05/2672015.html

floyd可以更新任意两点之间的关系,path[i][j]记录的是i的直接后驱,输出时直接递推得到字典序路径

#include <iostream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <stack>
#include <queue>
#include <cctype>
#include <vector>
#include <iterator>
#include <set>
#include <map>
#include <sstream>
using namespace std; #define mem(a,b) memset(a,b,sizeof(a))
#define pf printf
#define sf scanf
#define spf sprintf
#define pb push_back
#define debug printf("!\n")
#define MAXN 5010
#define MAX(a,b) a>b?a:b
#define blank pf("\n")
#define LL long long
#define ALL(x) x.begin(),x.end()
#define INS(x) inserter(x,x.begin())
#define pqueue priority_queue
#define INF 0x3f3f3f3f int n;
int g[][],path[][];
int b[],d[][]; void floyd()
{
int i,j,k;
int tmp;
for(i=;i<n;i++)
{
for(j=;j<n;j++)
{
path[i][j] = j;
d[i][j] = g[i][j];
}
} for(k=;k<n;k++)
{
for(i=;i<n;i++)
{
for(j=;j<n;j++)
{
tmp = d[i][k]+d[k][j]+b[k];
if(d[i][j]>tmp)
{
d[i][j] = tmp;
path[i][j] = path[i][k];
}
else if(tmp==d[i][j])
{
if(path[i][j]>path[i][k])
path[i][j]=path[i][k];
}
}
}
}
} int main()
{
int i,j;
while(sf("%d",&n)== && n)
{
mem(b,);
for(i=;i<n;i++)
{
for(j=;j<n;j++)
{
sf("%d",&g[i][j]);
if(g[i][j] == -)
g[i][j] = INF;
}
}
for(i=;i<n;i++)
sf("%d",&b[i]); floyd(); int s,t,tmp;
while(sf("%d%d",&s,&t)==)
{
if(s==- && t==-) break;
pf("From %d to %d :\n",s,t);
pf("Path: %d",s);
tmp=s-;
while(tmp!=t-)
{
pf("-->%d",path[tmp][t-]+);
tmp=path[tmp][t-];
}
blank;
pf("Total cost : %d\n\n",d[s-][t-]);
}
}
}