BZOJ2100
簡單的最短路.要用堆優化的dijkstra.當復習了.
code:
/************************************************************** Problem: 2100User: exponent Language: Pascal Result: Accepted Time:572 ms Memory:7356 kb ****************************************************************/ type edge=recordv,w,n:longint; end; const maxm=400000; maxn=100001; var e:array[0..maxm] of edge; h:array[0..maxm] of longint; head,d:array[0..maxn] of longint; vis:array[0..maxn] of boolean; n,m,home,pa,pb,u,v,w,i,ha,hb,ab,cnt,size:longint; procedure add(u,v,w:longint); begininc(cnt); e[cnt].v:=v; e[cnt].w:=w; e[cnt].n:=head[u]; head[u]:=cnt; end; procedure swap(a,b:longint); var temp:longint; begintemp:=h[a]; h[a]:=h[b]; h[b]:=temp; end; procedure down(k:longint); var p:longint; beginwhile k<=size>>1 dobeginp:=k<<1; if (p<size)and(d[h[p]]>d[h[p+1]]) then inc(p); if d[h[k]]>d[h[p]] thenbegin swap(k,p); k:=p; endelse break; end; end; procedure up(k:longint); beginwhile (k>1)and(d[h[k>>1]]>d[h[k]]) dobegin swap(k,k>>1); k:=k>>1; end; end; procedure ins(new:longint); begininc(size); h[size]:=new; up(size); end; procedure deltop; beginswap(1,size); dec(size); down(1); end; function dijk(s,t:longint):longint; var u,v,p:longint; beginfillchar(vis,sizeof(vis),0); fillchar(d,sizeof(d),127); size:=0; d[s]:=0; ins(s); while size>0 dobeginu:=h[1]; deltop; if vis[u] then continue; vis[u]:=true; p:=head[u]; while p<>0 dobeginv:=e[p].v; if d[v]>d[u]+e[p].w thenbegind[v]:=d[u]+e[p].w; ins(v); end; p:=e[p].n; end; end; exit(d[t]); end; function min(a,b:longint):longint; beginif a>b then exit(b); exit(a); end; beginreadln(m,n,home,pa,pb); for i:=1 to m dobeginreadln(u,v,w); add(u,v,w); add(v,u,w); end; ha:=dijk(home,pa); hb:=dijk(home,pb); ab:=dijk(pa,pb); writeln(min(ha,hb)+ab); end.轉載于:https://www.cnblogs.com/exponent/archive/2011/08/14/2137865.html
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