Prime adjacency table + priority queue

#include <iostream>#include<cmath>#include<cstring>#include<cstdlib>#include<cstdio>#include<algorithm>#include<vector>#include<queue>using namespacestd;#defineINF 0XFFFFFFF#defineMAXN 103structedge{intE, W; Edge (intE=0,intw=0): E (E), W (w) {} friendBOOL operator<(Edge A, Edge B) {returnA.W <B.W; }};vector<Edge>G[MAXN];intDIST[MAXN];BOOLVIS[MAXN];intm, N;intPrime () {Edge P, Pn; intNnode =0; dist[1] =0; Priority_queue< Edge >Q; Q.push (Edge (1,0) );  while( ! Q.empty () && Nnode <N) { while( !Q.empty ()) {P=Q.top ();            Q.pop (); if( !VIS[P.E]) Break; }        if(VIS[P.E])Continue; Nnode++; VIS[P.E]=true; intLen =g[p.e].size ();  for(intI=0; i<len; i++) {Pn=G[p.e][i]; if(!VIS[PN.E] && DIST[PN.E] >PN.W) {DIST[PN.E]=PN.W;            Q.push (Pn); }        }    }    if(Nnode <N)return-1; intsum =0;  for(intI=1; i<=n; i++) {sum+=Dist[i]; }    returnsum;}voidInit () { for(intI=0; i<=n; i++) {g[i].clear (); Dist[i]=INF; Vis[i]=false; }}intMain () { while(Cin >> M >>N, m)        {Init ();  for(intI=0; i<m; i++)        {            intA, B, C; CIN>> a >> b >>C;            G[a].push_back (Edge (b,c));        G[b].push_back (Edge (a,c)); }        intAns =Prime (); if(ans = =-1) cout<<"?"<<Endl; Elsecout<< ans <<Endl; }    return 0;}

Prime adjacency table + priority queue