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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;
}

posted @ 2011-06-20 16:32  金海峰  阅读(407)  评论(0编辑  收藏  举报