最小费用最大流模板

向总等编写的《奥赛经典·提高篇》上所给出的基本模板有误，现在把正确的模板贴上来。

Program MinCostMaxFlow;//By_Thispoet
Var
	c,f,cost				:Array[0..100,0..100]of Longint;
	a,b,ct					:Array[0..100]of Longint;
	ans						:Longint;
	i,j,k,m,n,p,q			:Longint;
	seq						:Array[1..10000]of Longint;
	h,t						:Longint;
	v						:Array[0..100]of Boolean;
	
Function Min(i,j:Longint):Longint;
begin
	if i<j then exit(i);exit(j);
end;
	
	
BEGIN

	readln(n,m);
	for i:=1 to m do
		begin
			read(j,k);
			readln(c[j,k],cost[j,k]);
		end;

	Repeat

		fillchar(v,sizeof(v),0);
		fillchar(ct,sizeof(ct),127);
		ct[0]:=0;
		v[0]:=true;
		a[0]:=-1;b[0]:=maxlongint;
		h:=0;t:=1;seq[1]:=0;
		while h<t do
			begin
				inc(h);k:=seq[h];
				for i:=1 to n+1 do
					if (f[k,i]<c[k,i])and(c[k,i]>0)and(ct[i]>ct[k]+cost[k,i])then
						begin
							inc(t);seq[t]:=i;
							a[i]:=k;b[i]:=Min(b[k],c[k,i]-f[k,i]);
							ct[i]:=ct[k]+cost[k,i];
							v[i]:=true;
						end else
							if (c[i,k]>0)and(f[i,k]>0)and(ct[i]>ct[k]-cost[i,k])then
								begin
									inc(t);seq[t]:=i;
									a[i]:=k;b[i]:=Min(b[k],f[i,k]);
									ct[i]:=ct[k]-cost[i,k];
									v[i]:=true;
								end;
			end;
		if v[n+1] then
			begin
				i:=n+1;
				while a[i]<>-1 do
					begin
						if (c[i,a[i]]>0)and(f[i,a[i]]>0) then
							begin
								dec(f[i,a[i]],b[n+1]);
								dec(ans,cost[i,a[i]]*b[n+1]);
							end else
								begin
									inc(f[a[i],i],b[n+1]);
									inc(ans,b[n+1]*cost[a[i],i]);
								end;
						i:=a[i];
					end;
			end;
		
	Until not v[n+1];
	
	writeln(ans);
	
END.