最短路四种基础算法模板题

poj2387  dijsktra模板题

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#define inf 0x3f3f3f3f
#define PI acos((double)-1)
using namespace std;

typedef long long ll;
const int maxn=2100;

int map[maxn][maxn],t,n,dist[maxn],vis[maxn];

void dijsktra()
{
    memset(vis,0,sizeof(vis));
    memset(dist,inf,sizeof(dist));
    dist[1]=0;
    for(int i=1;i<=n;i++)
    {
        int min=inf,k;
        for(int j=1;j<=n;j++)
        {
            if(dist[j]map[k][j]+min)
                dist[j]=map[k][j]+min;
        }
    }
    cout << dist[n] << endl;
}

int main()
{
    while(scanf("%d%d",&t,&n)!=EOF)
    {
        for(int i=1;i<=n;i++)
        {
            for(int j=1;j<=n;j++)
            {
                if(i==j)
                    map[i][j]=0;
                else
                    map[i][j]=map[j][i]=inf;
            }
        }
        for(int i=0;i

poj3660  floyd模板

#include 
#include 
#include 
#include 
#include 
using namespace std;

int map[101][101],n,m;

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

int main()
{
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        int cnt=0;
        memset(map,0,sizeof(map));
        for(int i=0;i

poj1860   判负权

bellman

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#define inf 0x3f3f3f3f
#define PI acos(double(-1))
using namespace std;

typedef long long ll;
const int maxn=110;
struct node
{
    int u,v;
    double r,c;
};
node e[maxn*maxn*2];
int n,m,vis[maxn],s,cnt,head[maxn],next[maxn*maxn*2];
double dist[maxn],v;

int bellman()
{
    for(int i=1;i<=n;i++)
        dist[i]=0;
    dist[s]=v;
    int flag;
    for(int i=0;i

spfa

#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#define inf 0x3f3f3f3f
#define PI acos(double(-1))
using namespace std;

typedef long long ll;
const int maxn=3000;
struct node
{
    int u,v;
    double r,c;
};
node e[maxn];
int n,m,vis[maxn],s,cnt,head[maxn],next[maxn],num[maxn];
double dist[maxn],v;

int spfa()
{
    queue q;
    for(int i=0;i<=n;i++)
        dist[i]=0;
    memset(vis,0,sizeof(vis));
    memset(num,0,sizeof(num));
    dist[s]=v;
    q.push(s);
    vis[s]=1;
    num[s]++;
    while(!q.empty())
    {
        int x=q.front();
        q.pop();
        vis[x]=0;
        for(int i=head[x];i!=-1;i=next[i])
        {
            if(dist[e[i].v]<(dist[x]-e[i].c)*e[i].r)
            {
                dist[e[i].v]=(dist[x]-e[i].c)*e[i].r;
                if(!vis[e[i].v])
                {
                    vis[e[i].v]=1;
                    q.push(e[i].v);
                    num[e[i].v]++;
                }
                if(num[e[i].v]>n)
                    return 1;
            }
        }
    }
    return 0;
}

int main()
{
    while(scanf("%d%d%d%lf",&n,&m,&s,&v)!=EOF)
    {
        cnt=0;
        memset(head,-1,sizeof(head));
        for(int i=0;i