poj2239
匈牙利，二分图匹配
View Code
#include
<
iostream
>
#include
<
cstdio
>
#include
<
cstdlib
>
#include
<
cstring
>
using
namespace
std;
#define
maxn 305
struct
Edge
{
int
v, next;
} edge[maxn
*
7
*
12
];
int
n, m;
int
head[maxn];
int
xM[maxn], yM[maxn];
bool
chk[maxn];
int
count;
void
addedge(
int
a,
int
b)
{
edge[count].next
=
head[a];
edge[count].v
=
b;
head[a]
=
count;
count
++
;
}
void
input()
{
int
t;
for
(
int
i
=
0
; i
<
n; i
++
)
{
scanf(
"
%d
"
,
&
t);
for
(
int
j
=
0
; j
<
t; j
++
)
{
int
p, q;
scanf(
"
%d%d
"
,
&
p,
&
q);
addedge(i, (p
-
1
)
*
12
+
q);
}
}
}
bool
SearchPath(
int
u)
{
for
(
int
i
=
head[u]; i
!=
-
1
; i
=
edge[i].next)
{
int
v
=
edge[i].v;
if
(
!
chk[v])
{
chk[v]
=
true
;
if
(yM[v]
==
-
1
||
SearchPath(yM[v]))
{
yM[v]
=
u;
xM[u]
=
v;
return
true
;
}
}
}
return
false
;
}
int
MaxMatch()
{
int
u, ret
=
0
;
memset(xM,
-
1
,
sizeof
(xM));
memset(yM,
-
1
,
sizeof
(yM));
for
(u
=
0
; u
<
n; u
++
)
if
(xM[u]
==
-
1
)
{
memset(chk,
false
,
sizeof
(chk));
if
(SearchPath(u))
ret
++
;
}
return
ret;
}
int
main()
{
//
freopen("t.txt", "r", stdin);
while
(scanf(
"
%d
"
,
&
n)
!=
EOF)
{
count
=
0
;
memset(head,
-
1
,
sizeof
(head));
m
=
7
*
12
+
1
;
input();
printf(
"
%d\n
"
, MaxMatch());
}
return
0
;
}