OJ-Problems-Source/HDOJ/3790_cnblogs.cpp

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#include <set>
#include <map>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <cctype>
#include <cstring>
#include <sstream>
#include <fstream>
#include <cstdlib>
#include <cassert>
#include <iostream>
#include <algorithm>
using namespace std;
//Constant Declaration
/*--------------------------*/
//#define LL long long
#define LL __int64
const int M=1100;//最多点数
const int INF=1<<30;
const double EPS = 1e-11;
const double PI = acos(-1.0);
/*--------------------------*/
// some essential funtion
/*----------------------------------*/
void Swap(int &a,int &b){ int t=a;a=b;b=t; }
int Max(int a,int b){ return a>b?a:b; }
int Min(int a,int b){ return a<b?a:b; }
int Gcd(int a,int b){ while(b){b ^= a ^=b ^= a %= b;} return a; }
/*----------------------------------*/
//for (i = 0; i < n; i++)
/*----------------------------------*/
struct djs
{
int l,p;
}d[M],g[M][M];
bool used[M];//标记i是否被用过
void init(int n)
{
int i, j;
for (i = 1; i <= n; i++)
{
for (j = 1; j <= n; j++)
{
g[i][j].l = INF;//初始化图没有边默认为INF,为了一定更新
g[i][j].p = INF;
}
}
for (i = 1; i <= n; i++)
{
d[i].l = INF;
d[i].p = INF;
}
memset(used, 0, sizeof(used));
}
int dijkstra(int star, int end, int n)//起点,终点,总点数(编号为1,2...n)
{
int min_num;//最小值的位置
int i;
d[star].l= 0;
d[star].p= 0;//起点到起点的最短距离为0很重要的一步
for (int cnt = 0; cnt < n; cnt++)//注意别用while(n--),这样会改变n的值。n次贪心
{
int min = INF;
for (i = 1; i <= n; i++)
{
if (!used[i] && d[i].l < min)
{
min = d[i].l;
min_num = i;
}
}
used[min_num] = 1;
//把d[min_num]作为中间点,对相邻的点做松弛
for (i = 1; i <= n; i++)
{
if (!used[i] && d[i].l > d[min_num].l + g[min_num][i].l)
{
d[i].l = d[min_num].l + g[min_num][i].l;
d[i].p = d[min_num].p + g[min_num][i].p;
}
if (!used[i] && d[i].l == d[min_num].l + g[min_num][i].l && d[i].p > d[min_num].p + g[min_num][i].p)//这里的判断是关键
{
d[i].p = d[min_num].p + g[min_num][i].p;
}
}
}
return d[end].l;
}
int main()
{
//freopen("in.txt","r",stdin);
//freopen("out.txt","w",stdout);
//int t, case1 = 0;
//scanf("%d", &t);
int n, m;
int i, j;
while (scanf("%d%d", &n, &m), n + m)
{
init(n);
for (i = 0; i < m; i++)
{
int a, b, c, c1;
scanf("%d%d%d%d", &a, &b, &c, &c1);
if (g[a][b].l > c)
{
g[b][a].l = g[a][b].l = c;
g[b][a].p= g[a][b].p = c1;
}//此题为无向图
if (g[a][b].l == c && g[b][a].p > c1)//这里的判断是关键
{
g[b][a].p= g[a][b].p = c1;
}
}
int star, end,ans;
scanf("%d%d", &star, &end);
ans = dijkstra(star, end, n);
printf("%d %d\n", ans, d[end].p);
}
return 0;
}