Zoj3229 shoot the bullet (maximum upstream/downstream stream with source sink)

#pragma warning(disable:4996)#include <iostream>#include <cstring>#include <string>#include <vector>#include <cstdio>#include <algorithm>#include <cmath>#include <queue>#include <map>#include <stack>using namespace std;#define maxn 3000#define maxe 700000#define inf 0x3f3f3f3fstruct Edge{int u, v, cap;int nxt;}edge[maxe];int head[maxn];struct Dicnic{int level[maxn];int iter[maxn];int add;void init(){add = 0; memset(head, -1, sizeof(head));memset(iter, -1, sizeof(iter));}void insert(int u, int v, int c){edge[add].u = u; edge[add].v = v; edge[add].cap = c;edge[add].nxt = head[u]; head[u] = add++;edge[add].u = v; edge[add].v = u; edge[add].cap = 0;edge[add].nxt = head[v]; head[v] = add++;}void bfs(int s){memset(level, -1, sizeof(level));queue<int> que;level[s] = 0;que.push(s);while (!que.empty()){int v = que.front(); que.pop();for (int i = head[v]; i != -1; i = edge[i].nxt){Edge &e = edge[i];if (e.cap > 0 && level[e.v] < 0){level[e.v] = level[v] + 1;que.push(e.v);}}}}int dfs(int v, int t, int f){if (v == t) return f;for (int &i = iter[v]; i != -1; i = edge[i].nxt){Edge &e = edge[i]; Edge &reve = edge[i ^ 1];if (e.cap > 0 && level[v] < level[e.v]){int d = dfs(e.v, t, min(f, e.cap));if (d>0){e.cap -= d; reve.cap += d;return d;}}}return 0;}int max_flow(int s, int t){int flow = 0;for (;;){bfs(s);if (level[t] < 0) return flow;memcpy(iter, head, sizeof(iter));int f;while ((f = dfs(s, t, inf))>0){flow += f;}}}}net;int n, m;int G[maxn];int mflow[400][1500];int main(){while (~scanf("%d%d", &n, &m)){int sum = 0;net.init();for (int i = 0; i < m; ++i) {scanf("%d", G + i); sum += G[i];}int s = n + m + 1, t = s + 1;int ss = t + 1, tt = ss + 1;int C, D;for (int i = 0; i < n; ++i){scanf("%d%d", &C, &D);net.insert(s, i, D);int t, l, r;for (int j = 0; j < C; ++j){scanf("%d%d%d", &t, &l, &r);mflow[i][t] = l;sum += l;net.insert(i, t + n, r - l);net.insert(ss, t + n, l);net.insert(i, tt, l);}}for (int i = 0; i < m; ++i){net.insert(i + n, t, inf);net.insert(ss, t, G[i]);net.insert(i + n, tt, G[i]);}net.insert(t, s, inf);if (net.max_flow(ss, tt) != sum){puts("-1\n"); continue;}net.insert(ss, s, inf);net.insert(t, tt, inf);int ans = net.max_flow(ss, tt);printf("%d\n", ans);stack<int> stk;int from, to, cap;for (int x = 0; x < n; ++x){for (int k = head[x]; ~k; k = edge[k].nxt){from = edge[k].u; to = edge[k].v; cap = edge[k ^ 1].cap;if (to >= n&&to < n + m){stk.push(cap + mflow[from][to - n]);//printf("%d\n", cap + mflow[from][to - n]);}}while (!stk.empty()){printf("%d\n", stk.top());stk.pop();}}puts("");}return 0;}