HYSBZ 1601(单点带值的最小生成树）

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题目大意：最小生成树

建源点0与各点连线的权为建水库的大小。

Program aa;var   n,i,j,p:longint;   u,v,w:array[0..100000] of longint;   size,cost:longint;   father:array[0..300] of longint;procedure qsort(l,r:longint);var   i,j,m,p:longint;begin   i:=l;j:=r;m:=w[(l+r) shr 1];   repeat      while w[i]<m do inc(i);      while w[j]>m do dec(j);      if i<=j then      begin         p:=w[i];w[i]:=w[j];w[j]:=p;         p:=u[i];u[i]:=u[j];u[j]:=p;         p:=v[i];v[i]:=v[j];v[j]:=p;         inc(i);dec(j);      end;   until i>j;   if l<j then qsort(l,j);   if i<r then qsort(i,r);end;function getfather(x:longint):longint;begin   if father[x]=x then exit(x);   father[x]:=getfather(father[x]);   exit(father[x]);end;begin   read(n);   for i:=1 to n do   begin      read(w[i]);      u[i]:=0;v[i]:=i;   end;   size:=n;   for i:=1 to n do      for j:=1 to n do      begin        read(p);        if i=j then continue;        inc(size);        u[size]:=i;v[size]:=j;w[size]:=p;      end;   qsort(1,size);   cost:=0;   for i:=0 to n do father[i]:=i;   for i:=1 to size do   begin      if (getfather(u[i])<>getfather(v[i])) then      begin         inc(cost,w[i]);         father[getfather(u[i])]:=father[getfather(v[i])];      end;   end;   writeln(cost);end.