标签:math sub base eof tor reg map return freopen
1 #define IOS ios_base::sync_with_stdio(0); cin.tie(0); 2 #include <cstdio>//sprintf islower isupper 3 #include <cstdlib>//malloc exit strcat itoa system("cls") 4 #include <iostream>//pair 5 #include <fstream>//freopen("C:\\Users\\13606\\Desktop\\草稿.txt","r",stdin); 6 #include <bitset> 7 //#include <map> 8 //#include<unordered_map> 9 #include <vector> 10 #include <stack> 11 #include <set> 12 #include <string.h>//strstr substr 13 #include <string> 14 #include <time.h>// srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9; 15 #include <cmath> 16 #include <deque> 17 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less 18 #include <vector>//emplace_back 19 //#include <math.h> 20 #include <cassert> 21 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor 22 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare) 23 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation 24 //****************** 25 int abss(int a); 26 int lowbit(int n); 27 int Del_bit_1(int n); 28 int maxx(int a,int b); 29 int minn(int a,int b); 30 double fabss(double a); 31 void swapp(int &a,int &b); 32 clock_t __STRAT,__END; 33 double __TOTALTIME; 34 void _MS(){__STRAT=clock();} 35 void _ME(){__END=clock();__TOTALTIME=(double)(__END-__STRAT)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;} 36 //*********************** 37 #define rint register int 38 #define fo(a,b,c) for(rint a=b;a<=c;++a) 39 #define fr(a,b,c) for(rint a=b;a>=c;--a) 40 #define mem(a,b) memset(a,b,sizeof(a)) 41 #define pr printf 42 #define sc scanf 43 #define ls rt<<1 44 #define rs rt<<1|1 45 typedef vector<int> VI; 46 typedef long long ll; 47 const double E=2.718281828; 48 const double PI=acos(-1.0); 49 //const ll INF=(1LL<<60); 50 const int inf=(1<<30); 51 const double ESP=1e-9; 52 const int mod=(int)1e9+7; 53 const int N=(int)2e5+10; 54 55 class DINIC 56 { 57 public: 58 // const int MAXN=10004,MAXWAY=100005; 59 int n,way,max_flow,deep[N]; 60 int tot,head[N],cur[N]; 61 struct EDGE{ 62 int to,next; 63 int dis; 64 }edge[N]; 65 void Init(int n) 66 { 67 tot=-1;//因为加反向边要^1,所以要从0开始; 68 for(int i=0;i<=n;++i) 69 head[i]=-1; 70 } 71 void add(int from,int to,int cost,bool flag) 72 { 73 ++tot; 74 edge[tot].to=to; 75 edge[tot].dis=0; 76 if(flag)edge[tot].dis=cost; 77 edge[tot].next=head[from]; 78 head[from]=tot; 79 } 80 queue<int>q; 81 bool bfs(int s,int t) 82 { 83 for(int i=1;i<=n;++i) 84 deep[i]=inf; 85 while(!q.empty())q.pop(); 86 for(int i=1;i<=n;++i)cur[i]=head[i]; 87 deep[s]=0; 88 q.push(s); 89 90 while(!q.empty()) 91 { 92 int now=q.front();q.pop(); 93 for(int i=head[now];i!=-1;i=edge[i].next) 94 { 95 if(deep[edge[i].to]==inf&&edge[i].dis) 96 { 97 deep[edge[i].to]=deep[now]+1; 98 q.push(edge[i].to); 99 } 100 } 101 } 102 return deep[t]<inf; 103 } 104 int dfs(int now,int t,int limit) 105 { 106 if(!limit||now==t)return limit; 107 int flow=0,f; 108 for(int i=cur[now];i!=-1;i=edge[i].next) 109 { 110 cur[now]=i; 111 if(deep[edge[i].to]==deep[now]+1&&(f=dfs(edge[i].to,t,min(limit,edge[i].dis)))) 112 { 113 flow+=f; 114 limit-=f; 115 edge[i].dis-=f; 116 edge[i^1].dis+=f; 117 if(!limit)break; 118 } 119 } 120 return flow; 121 } 122 void Dinic(int s,int t) 123 { 124 while(bfs(s,t)) 125 max_flow+=dfs(s,t,inf); 126 } 127 }G; 128 129 int main() 130 { 131 int S,T; 132 sc("%d%d%d%d",&G.n,&G.way,&S,&T); 133 G.Init(G.n); 134 for(int i=1;i<=G.way;++i) 135 { 136 int u,v,cost; 137 sc("%d%d%d",&u,&v,&cost); 138 G.add(u,v,cost,1); 139 G.add(v,u,cost,0); 140 } 141 G.Dinic(S,T); 142 pr("%d\n",G.max_flow); 143 return 0; 144 } 145 146 /**************************************************************************************/ 147 148 int maxx(int a,int b) 149 { 150 return a>b?a:b; 151 } 152 153 void swapp(int &a,int &b) 154 { 155 a^=b^=a^=b; 156 } 157 158 int lowbit(int n) 159 { 160 return n&(-n); 161 } 162 163 int Del_bit_1(int n) 164 { 165 return n&(n-1); 166 } 167 168 int abss(int a) 169 { 170 return a>0?a:-a; 171 } 172 173 double fabss(double a) 174 { 175 return a>0?a:-a; 176 } 177 178 int minn(int a,int b) 179 { 180 return a<b?a:b; 181 }
标签:math sub base eof tor reg map return freopen
原文地址:https://www.cnblogs.com/--HPY-7m/p/11741878.html