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97 lines
1.6 KiB
97 lines
1.6 KiB
/*
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* Max flow EK with DFS.
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*/
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const int INF = 0x70000000;
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int size[10];
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int to[10][10];
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int cap[10][10];
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int rev[10][10];
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int used[10];
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void my_memset(int arr[], int val, int n)
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{
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int i = 0;
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while (i < n) {
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arr[i] = val;
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i = i + 1;
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}
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}
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void add_node(int u, int v, int c)
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{
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to[u][size[u]] = v;
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cap[u][size[u]] = c;
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rev[u][size[u]] = size[v];
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to[v][size[v]] = u;
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cap[v][size[v]] = 0;
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rev[v][size[v]] = size[u];
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size[u] = size[u] + 1;
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size[v] = size[v] + 1;
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}
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int dfs(int s, int t, int f)
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{
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if (s == t)
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return f;
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used[s] = 1;
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int i = 0;
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while (i < size[s]) {
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if (used[to[s][i]]) { i = i + 1; continue; }
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if (cap[s][i] <= 0) { i = i + 1; continue; }
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int min_f;
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if (f < cap[s][i])
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min_f = f;
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else
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min_f = cap[s][i];
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int d = dfs(to[s][i], t, min_f);
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if (d > 0) {
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cap[s][i] = cap[s][i] - d;
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cap[to[s][i]][rev[s][i]] = cap[to[s][i]][rev[s][i]] + d;
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return d;
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}
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i = i + 1;
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}
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return 0;
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}
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int max_flow(int s, int t)
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{
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int flow = 0;
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while (1) {
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my_memset(used, 0, 10);
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int f = dfs(s, t, INF);
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if (f == 0)
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return flow;
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flow = flow + f;
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}
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}
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int main()
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{
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int V, E;
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V = getint();
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E = getint();
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my_memset(size, 0, 10);
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while (E > 0) {
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int u, v;
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u = getint();
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v = getint();
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int c = getint();
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add_node(u, v, c);
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E = E - 1;
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}
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putint(max_flow(1, V));
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putch(10);
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return 0;
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}
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