不知道为什么只有 #1 过不去
正确输出 2,程序输出 4
#include<bits/stdc++.h>
/*
#pragma GCC optimize(3)
#pragma GCC optimize("Ofast,no-stack-protector")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("inline")
#pragma GCC optimize("-fgcse")
#pragma GCC optimize("-fgcse-lm")
#pragma GCC optimize("-fipa-sra")
#pragma GCC optimize("-ftree-pre")
#pragma GCC optimize("-ftree-vrp")
#pragma GCC optimize("-fpeephole2")
#pragma GCC optimize("-ffast-math")
#pragma GCC optimize("-fsched-spec")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-falign-jumps")
#pragma GCC optimize("-falign-loops")
#pragma GCC optimize("-falign-labels")
#pragma GCC optimize("-fdevirtualize")
#pragma GCC optimize("-fcaller-saves")
#pragma GCC optimize("-fcrossjumping")
#pragma GCC optimize("-fthread-jumps")
#pragma GCC optimize("-funroll-loops")
#pragma GCC optimize("-fwhole-program")
#pragma GCC optimize("-freorder-blocks")
#pragma GCC optimize("-fschedule-insns")
#pragma GCC optimize("inline-functions")
#pragma GCC optimize("-ftree-tail-merge")
#pragma GCC optimize("-fschedule-insns2")
#pragma GCC optimize("-fstrict-aliasing")
#pragma GCC optimize("-fstrict-overflow")
#pragma GCC optimize("-falign-functions")
#pragma GCC optimize("-fcse-skip-blocks")
#pragma GCC optimize("-fcse-follow-jumps")
#pragma GCC optimize("-fsched-interblock")
#pragma GCC optimize("-fpartial-inlining")
#pragma GCC optimize("no-stack-protector")
#pragma GCC optimize("-freorder-functions")
#pragma GCC optimize("-findirect-inlining")
#pragma GCC optimize("-fhoist-adjacent-loads")
#pragma GCC optimize("-frerun-cse-after-loop")
#pragma GCC optimize("inline-small-functions")
#pragma GCC optimize("-finline-small-functions")
#pragma GCC optimize("-ftree-switch-conversion")
#pragma GCC optimize("-foptimize-sibling-calls")
#pragma GCC optimize("-fexpensive-optimizations")
#pragma GCC optimize("-funsafe-loop-optimizations")
#pragma GCC optimize("inline-functions-called-once")
#pragma GCC optimize("-fdelete-null-pointer-checks")
#pragma GCC optimize("-fdelete-null-pointer-checks,inline-functions-called-once,-funsafe-loop-optimizations,-fexpensive-optimizations,-foptimize-sibling-calls,-ftree-switch-conversion,-finline-small-functions,inline-small-functions,-frerun-cse-after-loop,-fhoist-adjacent-loads,-findirect-inlining,-freorder-functions,no-stack-protector,-fpartial-inlining,-fsched-interblock,-fcse-follow-jumps,-fcse-skip-blocks,-falign-functions,-fstrict-overflow,-fstrict-aliasing,-fschedule-insns2,-ftree-tail-merge,inline-functions,-fschedule-insns,-freorder-blocks,-fwhole-program,-funroll-loops,-fthread-jumps,-fcrossjumping,-fcaller-saves,-fdevirtualize,-falign-labels,-falign-loops,-falign-jumps,unroll-loops,-fsched-spec,-ffast-math,Ofast,inline,-fgcse,-fgcse-lm,-fipa-sra,-ftree-pre,-ftree-vrp,-fpeephole2",3)
*/
using namespace std;
typedef long long ll;
namespace IO{
char buf[1 << 20], *p1 = buf, *p2 = buf;
#define getchar() (p1 == p2 && (p2 = (p1 = buf) + \
fread(buf, 1, 1 << 20, stdin), p1 == p2) ? EOF : *p1++)
inline ll read(){
ll x = 0,h = 1;
char ch = getchar();
while(!(ch=='-'||('0'<=ch&&ch<='9'))) ch = getchar();
if(ch=='-') h = -1;
else x = ch-'0';
ch = getchar();
while('0'<=ch&&ch<='9'){
x = x*10+ch-'0';
ch = getchar();
}
return x*h;
}
inline ll digread(){
char ch = getchar();
while(!('0'<=ch&&ch<='9')) ch = getchar();
return ch-'0';
}
inline char readCH(){
char ch = getchar();
while(!(ch=='x')) ch = getchar();
return ch;
}
inline void print(ll x){
if(x>9) print(x/10);
putchar(x%10+'0');
}
inline void write(ll x){
if(x<0) putchar('-'),x = -x;
print(x);
}
}
using namespace IO;
#define File(name) \
freopen(#name ".in", "r", stdin); \
freopen(#name ".out", "w", stdout);
#define ERR assert(0)
#define RunTime ((double)clock()/CLOCKS_PER_SEC)
/*
有时候程序没反应就把 IO 里面重定义 getchar 删掉
-std=c++11 -Wall -Wextra -Wl,--stack=102400000000 -fno-ms-extensions
找不出来哪错了要检查 RE 问题,比如数组开小了,越界,函数返回值 这一条非常重要!
用 long long TLE 可以尝试换成 int
对 vector 进行修改时,要 for(auto &v : vec) v++。必须加 &
n 行 m 列的矩阵先从左到右在从上到下编号,第 i 行 j 列是 (i-1)*m+j
网络流建图正边反边一定连着建
*/
const ll N = 10000010;
const ll INF = 1e16;
struct Edge{
ll from,to,val,nxt;
//bool operator <(const Edge &x) const{
// return val<x.val;
//}
} edge[N];
ll D = 0;
ll s,t;
ll head[N],cnt = 1;
ll dis[N],cur[N];
ll dfs(ll id,ll flw){
if(id==t) return flw;
ll ret = 0;
for(ll i = cur[id]; i&&flw>0; i = edge[i].nxt){
cur[id] = i;
ll v = edge[i].to;
if(edge[i].val>0&&dis[v]==dis[id]+1){
ll diff = dfs(v,min(flw,edge[i].val));
if(diff==0) dis[v] = INF;
edge[i].val-=diff;
edge[i^1].val+=diff;
ret+=diff;
flw-=diff;
}
}
return ret;
}
bool bfs(ll id){
for(ll i = 1; i <= D; i++) dis[i] = INF;
queue<ll> q;
q.push(id);
dis[id] = 0;
cur[id] = head[id];
while(!q.empty()){
ll fir = q.front();
q.pop();
for(ll i = head[fir]; i; i = edge[i].nxt){
ll v = edge[i].to;
if(edge[i].val>0&&dis[v]==INF){
q.push(v);
cur[v] = head[v];
dis[v] = dis[fir]+1;
if(v==t) return 1;
}
}
}
return 0;
}
ll Dinic(){
ll ans = 0;
while(bfs(s)) ans+=dfs(s,INF);
return ans;
}
void AddEdge(ll u,ll v,ll w){
cnt++;
edge[cnt].from = u,edge[cnt].to = v,edge[cnt].val = w;
edge[cnt].nxt = head[u],head[u] = cnt;
}
void add(ll u,ll v,ll w){
AddEdge(u,v,w);
AddEdge(v,u,0);
}
ll n,m;
Edge osu[N];
void ReSetAll(){
memset(head,0,sizeof(head));
memset(dis,0,sizeof(dis));
memset(cur,0,sizeof(cur));
cnt = 1;
}
int main(){
n = read(),m = read();
for(ll i = 1; i <= m; i++) osu[i].from = read(),osu[i].to = read(),osu[i].val = read();
//sort(osu+1,osu+m+1);
D = n;
ll u0 = read(),v0 = read(),L = read(),ans = 0;
s = u0,t = v0;
for(ll i = 1; i <= m; i++) if(osu[i].val<L) add(osu[i].from,osu[i].to,1),add(osu[i].to,osu[i].from,1);
ans+=Dinic();
//printf("%lld\n",ans);return 0;
ReSetAll();
for(ll i = 1; i <= m; i++) if(osu[i].val>=L) add(osu[i].from,osu[i].to,1),add(osu[i].to,osu[i].from,1);
ans+=Dinic();
printf("%lld\n",ans);
fprintf(stderr, "TIME:%.3lf s\n", RunTime);
return 0;
}
/*
*/