bzoj 1191 匈牙利算法

只需要做一遍匈牙利，只要有一个没法匹配上就break就行了

/**************************************************************
    Problem: 1191
    User: BLADEVIL
    Language: Pascal
    Result: Accepted
    Time:12 ms
    Memory:256 kb
****************************************************************/
 
//By BLADEVIL
var
    flag                    :array[0..1010] of boolean;
    link                    :array[0..1010] of longint;
    n, m                    :longint;
    pre, other, last        :array[0..2020] of longint;
    l                       :longint;
    ans                     :longint;
     
procedure connect(x,y:longint);
begin
    inc(l);
    pre[l]:=last[x];
    last[x]:=l;
    other[l]:=y;
end;
     
procedure init;
var
    i                       :longint;
    x, y                    :longint;
begin
    read(n,m);
    for i:=1 to m do
    begin
        read(x,y);
        connect(i,x);
        connect(i,y);
    end;
end;
 
function find(x:longint):boolean;
var
    i                       :longint;
    q, p                    :longint;
begin
    q:=last[x];
    while q<>0 do
    begin
        p:=other[q];
        if not flag[p] then
        begin
            flag[p]:=true;
            if (link[p]=0) or (find(link[p])) then
            begin
                link[p]:=x;
                exit(true);
            end;
        end;
        q:=pre[q];
    end;
    exit(false);
end;
 
procedure main;
var
    i                       :longint;
begin
    ans:=0;
    for i:=1 to m do
    begin
        fillchar(flag,sizeof(flag),false);
        if find(i) then inc(ans) else break;
    end;
    writeln(ans);
end;
 
begin
    init;
    main;
end.