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    scanf在使用时,%[],中括号中的多个字符用逗号隔开

    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;
    }

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  • 原文地址:https://www.cnblogs.com/rainydays/p/2085327.html
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