参考:http://blog.csdn.net/wiking__acm/article/details/40185509
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
using namespace std;
const int maxn = 1e3 + 5;
const int INF = 1e9;
const double eps = 1e-6;
typedef unsigned long long ULL;
typedef long long LL;
typedef pair<int, int> P;
#define fi first
#define se second
struct Edge {
int from, to, cap, flow, cost;
};
struct MCMF {
int n, m, s, t;
vector edges;
vector<int> G[maxn];
int inq[maxn]; // 是否在队列中
int d[maxn]; // Bellman-Ford,单位流量的费用
int p[maxn]; // 上一条弧
int a[maxn]; // 可改进量
void init(int n) {
this->n = n;
for(int i = 0; i < n; i++) G[i].clear();
edges.clear();
}
void AddEdge(int from, int to, int cap, int cost) {
edges.push_back((Edge){from, to, cap, 0, cost});
edges.push_back((Edge){to, from, 0, 0, -cost});
m = edges.size();
G[from].push_back(m-2);
G[to].push_back(m-1);
}
bool BellmanFord(int s, int t, int &flow,int &cost) {
for(int i = 0; i < n; i++) d[i] = INF;
memset(inq, 0, sizeof(inq));
d[s] = 0; inq[s] = 1; p[s] = 0; a[s] = INF;
queue<int> Q;
Q.push(s);
while(!Q.empty()) {
int u = Q.front(); Q.pop();
inq[u] = 0;
for(int i = 0; i < G[u].size(); i++) {
Edge& e = edges[G[u][i]];
if(e.cap > e.flow && d[e.to] > d[u] + e.cost) {
d[e.to] = d[u] + e.cost;
p[e.to] = G[u][i];
a[e.to] = min(a[u], e.cap - e.flow);
if(!inq[e.to]) { Q.push(e.to); inq[e.to] = 1; }
}
}
}
if(d[t] == INF) return false;//s-t不连通,失败退出
flow += a[t];
cost += d[t] * a[t];
int u = t;
while(u != s) {
edges[p[u]].flow += a[t];
edges[p[u]^1].flow -= a[t];
u = edges[p[u]].from;
}
return true;
}
// 需要保证初始网络中没有负权圈
int Mincost(int s, int t, int& flow) {
int cost = 0;
while(BellmanFord(s, t,flow, cost));
return cost;
}
void print(int tot){
for(int i=tot;i>=1;--i){
int e=G[i+tot][0];
int flow=edges[e].flow;
if(flow==0){
int fg=1;
int pos=i;
vector<int>path;
path.push_back(i);
while(fg){
fg=0;
for(int i=0;iint e=G[pos][i];
int flow=edges[e].flow;
if(flow!=0&&edges[e].to>tot){
fg=1;
pos=edges[e].to-tot;
path.push_back(pos);
break;
}
}
}
printf("%d",path.size());
for(int i=0;iprintf(" %d",path[i]);
}
puts("");
}
}
}
};
MCMF solver;
int main(){
int n, m;
while(scanf("%d%d", &n, &m) != EOF){
solver.init(2*n+5);
int source = 0, sink = 2*n+1;
for(int i = 1;i <= n;i++){
solver.AddEdge(source, i, 1, 0);
solver.AddEdge(i+n, sink, 1, 0);
}
while(m--){
int x, y, c;
scanf("%d%d%d", &x, &y, &c);
solver.AddEdge(x, y+n, 1, c);
}
int flow = 0;
int cost = solver.Mincost(source, sink, flow);
printf("%d %d\n", n-flow, cost);
solver.print(n);
}
return 0;
}