2015 Multi-school joint training first field tricks Device (hdu5294)

Test instructions: Give a graph, give the starting point S, the end point T, the minimum to remove a few edges so that s can not t, up to a few edges so that s to T
Ideas:
First, run one side shortest way, record shortest number of sides in short circuit, total number of sides-the shortest number of sides is the second answer
The first answer is to ask for the smallest cut in the shortest way, that is, to find the maximum flow, and then build a new map based on the short circuit, right 1, run one side of the network stream

Template problem, the template is used in the future

#include <iostream>#include <cstdio>#include <cstring>#include <queue>#include <vector>using namespace STD;Const intINF =0x7f7f7f;Const intMAXM =12e4+5;Const intMAXN =2e3+5;intN, M;structEdge {intTo, W, next;} EDGE[MAXM];intTot, HEAD[MAXN];voidAddedge (intUintVintW) {edge[tot].to = v;    EDGE[TOT].W = W;    Edge[tot].next = Head[u];    Head[u] = tot++;    edge[tot].to = u;    EDGE[TOT].W = W;    Edge[tot].next = Head[v]; HEAD[V] = tot++;}intDIS[MAXN], VIS[MAXN];intMINB[MAXN];intSPFA (ints) {memset(Dis,0x3f,sizeof(dis));memset(Vis,0,sizeof(VIS));memset(MINB,0x3f,sizeof(MINB)); Queue<int>Q Dis[s] =0; Minb[s] =0; Vis[s] =1; Q.push (s); while(!q.empty ()) {intU = Q.front ();        Q.pop (); Vis[u] =0; for(inti = Head[u]; ~i; i = edge[i].next) {intv = edge[i].to, w = EDGE[I].W;if(Dis[v] = = Dis[u] + W) {Minb[v] = min (Minb[v], Minb[u] +1);if(!vis[v]) {Vis[v] =1;                Q.push (v); }            }if(Dis[v] > Dis[u] + W)                {Dis[v] = Dis[u] + W; MINB[V] = Minb[u] +1;if(!vis[v]) {Vis[v] =1;                Q.push (v); }            }        }    }}structEg {intU, cap, rev; Eg (intUuintCcintRR) {u = uu; cap = cc; rev = RR; }}; vector<Eg>G[MAXN];BOOLUSED[MAXN];voidAddintUintVintCAP) {G[u].push_back (Eg (V, Cap, g[v].size ())); G[v].push_back (Eg (U,0, G[u].size ()-1));}voidBuild () { for(inti =1; I <= N; ++i) { for(intj = Head[i]; ~j; j = edge[j].next) {intv = edge[j].to, w = EDGE[J].W;if(Dis[v]-dis[i] = = W) {Add (I, V,1); }        }    }}intDfsintVintTintf) {if(v = = t)returnF USED[V] =true; for(inti =0; I < g[v].size (); ++i) {Eg &e = g[v][i];if(!USED[E.U] && e.cap >0) {intD = DFS (E.U, T, Min (f, e.cap));if(D >0) {e.cap-= D; G[e.u][e.rev].cap + = D;returnD }        }    }return 0;}intMax_flow (intSintT) {intFlow =0; while(1) {memset(Used,0,sizeof(used));intF = DFS (S, T, INF);if(f = =0)returnFlow    Flow + + F; }}voidInit () {tot =0;memset(Head,-1,sizeof(head)); for(inti =0; I <= N;    ++i) {g[i].clear (); }}intMain () {//freopen ("in", "R", stdin);     while(~scanf("%d%d", &n, &m)) {init (); for(inti =0; I < m; ++i) {intU, V, W;scanf(" %d%d%d", &u, &v, &w);        Addedge (U, V, W); } SPFA (1); Build ();intAns = max_flow (1, n);printf("%d%d\n", ans, m-minb[n]); }return 0;}

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2015 Multi-school joint training first field tricks Device (hdu5294)