網絡流

scanf在使用時，%［］,中括號中的多個字符用逗號隔開

View Code #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;
} 超強干貨來襲 云風專訪：近40年碼齡，通宵達旦的技術人生

總結

以上是生活随笔為你收集整理的poj1459的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。