poj1459
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scanf在使用时，%［］,中括号中的多个字符用逗号隔开
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#include
<
iostream
>
#include
<
cstdio
>
#include
<
cstdlib
>
#include
<
cstring
>
using
namespace
std;
#define
maxn 105
#define
inf 0x3f3f3f3f
struct
edge
{
int
x, y, nxt, c;
} bf[(maxn
*
maxn
+
maxn)
*
2
];
int
n, m, p, con, s, t;
int
head[maxn], cur[maxn], ps[maxn], dep[maxn], ne;
void
addedge(
int
x,
int
y,
int
c)
{
bf[ne].x
=
x;
bf[ne].y
=
y;
bf[ne].c
=
c;
bf[ne].nxt
=
head[x];
head[x]
=
ne
++
;
bf[ne].x
=
y;
bf[ne].y
=
x;
bf[ne].c
=
0
;
bf[ne].nxt
=
head[y];
head[y]
=
ne
++
;
}
void
input()
{
char
st[
100
];
int
a, b, c;
s
=
n;
t
=
n
+
1
;
n
+=
2
;
ne
=
2
;
memset(head,
0
,
sizeof
(head));
for
(
int
i
=
0
; i
<
m; i
++
)
{
scanf(
"
%[^(]
"
, st);
scanf(
"
(%d,%d)%d
"
,
&
a,
&
b,
&
c);
addedge(a, b, c);
}
for
(
int
i
=
0
; i
<
p; i
++
)
{
scanf(
"
%[^(]
"
, st);
scanf(
"
(%d)%d
"
,
&
a,
&
b);
addedge(s, a, b);
}
for
(
int
i
=
0
; i
<
con; i
++
)
{
scanf(
"
%[^(]
"
, st);
scanf(
"
(%d)%d
"
,
&
a,
&
b);
addedge(a, t, b);
}
}
int
flow()
{
int
tr, res
=
0
;
int
i, j, k, f, r, top;
while
(
1
)
{
memset(dep,
-
1
, n
*
sizeof
(
int
));
for
(f
=
dep[ps[
0
]
=
s]
=
0
, r
=
1
; f
!=
r;)
for
(i
=
ps[f
++
], j
=
head[i]; j; j
=
bf[j].nxt)
{
if
(bf[j].c
&&
-
1
==
dep[k
=
bf[j].y])
{
dep[k]
=
dep[i]
+
1
;
ps[r
++
]
=
k;
if
(k
==
t)
{
f
=
r;
break
;
}
}
}
if
(
-
1
==
dep[t])
break
;
memcpy(cur, head, n
*
sizeof
(
int
));
for
(i
=
s, top
=
0
;;)
{
if
(i
==
t)
{
for
(k
=
0
, tr
=
inf; k
<
top;
++
k)
if
(bf[ps[k]].c
<
tr)
tr
=
bf[ps[f
=
k]].c;
for
(k
=
0
; k
<
top;
++
k)
bf[ps[k]].c
-=
tr, bf[ps[k]
^
1
].c
+=
tr;
res
+=
tr;
i
=
bf[ps[top
=
f]].x;
}
for
(j
=
cur[i]; cur[i]; j
=
cur[i]
=
bf[cur[i]].nxt)
if
(bf[j].c
&&
dep[i]
+
1
==
dep[bf[j].y])
break
;
if
(cur[i])
{
ps[top
++
]
=
cur[i];
i
=
bf[cur[i]].y;
}
else
{
if
(
0
==
top)
break
;
dep[i]
=
-
1
;
i
=
bf[ps[
--
top]].x;
}
}
}
return
res;
}
int
main()
{
//
freopen("t.txt", "r", stdin);
while
(scanf(
"
%d%d%d%d
"
,
&
n,
&
p,
&
con,
&
m)
!=
EOF)
{
input();
int
ans
=
flow();
printf(
"
%d\n
"
, ans);
}
return
0
;
}