hdu2962 (Shortest circuit + two points)

Test instructions: The shortest way under the maximum height, because the topic gives the limit high, so we only need two points height and then use SPFA

#include <iostream> #include <string.h> #include <queue> #include <vector> #include <utility > #include <cstdio> #include <cstring> #include <algorithm>using namespace std; #define N 205#define  MAXN 2005const int INF = 9999999;int ht[maxn][maxn];int mp[maxn][maxn];int d[maxn];int mid_ht;int n,m;int used[maxn];void    SPFA (int s) {fill (d,d+n+1,inf);    Queue<int> que;    Fill (used,used+n+1,0);    D[s] = 0;    Que.push (s);        while (!que.empty ()) {int u = que.front (); Que.pop ();        Used[u] = 0;            for (int i = 1; I <= n; i++) {if (Ht[u][i] >= mid_ht && ht[u][i]| | ht[u][i] = = 1)                   {if (D[i] > D[u] + mp[u][i]) {d[i] = D[u] + mp[u][i];                       if (!used[i]) {used[i] = 1;                   Que.push (i); }}}}}}int main () {#ifdef XXZ freopen ("In.txt", "R", stdin);    #endif//XXZ int a,b,c,e;    int case = 1;        while (~SCANF ("%d%d", &n,&m)) {if (n = = 0 && m== 0) break;            for (int i = 0; I <= N; i++) {fill (mp[i],mp[i]+n+1,inf);        Fill (ht[i],ht[i]+n+1,0);            } for (int i = 0; i < m; i++) {scanf ("%d%d%d%d", &a,&b,&c,&e);            MP[A][B] = mp[b][a] = e;        HT[A][B] = ht[b][a] = C;        } int start,end,h;        scanf ("%d%d%d", &start,&end,&h);        int L = 0, r = h;        int ans = 0, ans2 = INF;            while (L <= r) {mid_ht = (l+r)/2;            SPFA (start);            if (d[end] = = INF) {r = mid_ht-1;                    } else {if (ans < mid_ht) {ans = mid_ht;                Ans2 = D[end]; } else if (ans = = Mid_ht && D[end] &lT                ANS2)//Pay attention to this item when the height is considered at the same time as the smaller path {ans2 = D[end];            } L = mid_ht+1;        }} if (case >1) printf ("\ n");//otherwise PE printf ("Case%d:\n", case++);        if (ans2 = = INF | | ans = = 0) {printf ("Cannot reach destination\n");            } else {printf ("Maximum height =%d\n", ans);        printf ("Length of shortest route =%d\n", ans2); }} return 0;}

hdu2962 (Shortest circuit + two points)