spfa经过deque（双向队列）优化后的模板

                        spfa经过deque（双向队列）优化后的模板

//C 
#include <stdio.h> 
#include <stdlib.h> 
#include <math.h> 
#include <string.h> 
#include <ctype.h> 
#include <time.h> 
//C++ 
#include <iostream> 
#include <algorithm> 
#include <queue> 
#include <vector> 
#include <map> 
#include <list> 
using namespace std; 
 
//start 
//C 
typedef long long LL; 
//typedef __int64 LL;
#define INF 0x7F7F7F7F 
#define HEAD 100 
#define EDGE 10000 
#define eps 1e-8 
 
typedef pair <int , int> PII;
#define MP make_pair
 
#define CLEAR(a,b) memset ( a , b , sizeof ( a ) ) 
#define CLEARN(a,b,s,size) memset ( a + s , b , sizeof size ) 
 
#define FOR(a,b,i) for ( i = a ; i < b ; i++ ) 
#define FORB(b,a,i) for ( i = b ; i > a ; i-- ) 
#define FORE(a,b,i) for ( i = a ; i <= b ; i++ ) 
#define FOREB(b,a,i) for ( i = b ; i >= a ; i-- ) 
#define FORN(a,b,i,nc) for ( i = a ; i < b ; i += nc ) 
#define FORNB(b,a,i,nc) for ( i = b ; i > a ; i -= nc ) 
#define FOREN(a,b,i,nc) for ( i = a ; i <= b ; i += nc ) 
#define FORENB(b,a,i,nc) for ( i = b ; i >= a ; i -= nc ) 
 
#define COPY(a,b,lt,rt,i) for ( i = lt ; i <= rt ; i++ ) a[i] = b[i]; 
 
#define sqr(a,b) sqrt ( (double) a * a + (double) b * b ) 
 
//c++ 
template <class T> inline T INT_LEN( T v ) { int len = 1 ; while ( v /= 10 ) ++len; return len; } 
 
//#define LocalHost 
 
int M = EDGE;
 
bool vis[HEAD];
 
int dis[HEAD] , q[EDGE];
 
int N;
 
void spfa ( int * head , re * edge , int s , int M ){   // re 为a边À?的Ì?类¤¨¤型¨ª
    int i , u , v , front = 0 , rear = 1 ; 
    CLEAR ( vis , 0 ); 
    CLEAR ( dis , 0x7f );
    dis[s] = 0; 
    q[0] = s; 
    while ( front != rear ){ 
        u = q[front++] ; 
        if ( front == M ) front = 0; 
        vis[u] = false; 
        for ( i = head[u] ; ~i ; i = edge[i].nxt ){ 
            v = edge[i].v; 
            if ( dis[v] > dis[u] + edge[i].w ){ 
                dis[v] = dis[u] + edge[i].w ; 
                if ( !vis[v] ){ 
                    vis[v] = true;
                    if ( dis[v] > dis[q[front]] ){
                        q[rear++] = v; 
                        if ( rear == M ) rear = 0; 
                    }
                    else {
                        if ( --front < 0 ) front = ~-M;
                        q[front] = v;
                    }
                } 
            } 
        } 
    } 
} 

 转载自：http://blog.sina.com.cn/s/blog_64018c250100xbaz.html