這種轉(zhuǎn)換是錯誤的，最大流都改變了。

```C++

//Luogu?P1344?[USACO4.4]追查壞牛奶Pollutant?Control

#include?<iostream>

#include?<cstring>

#include?<algorithm>

#include?<queue>

#define?N?10010

#define?M?200010

#define?debug?printf("%d?%s\n",__LINE__,__FUNCTION__)

typedef?long?long?ll,?i64,?LL;

const?ll?LNF?=?0x3f3f3f3f3f3f3f3f;

using?namespace?std;

const?int?mod?=?2019;

int?S,?T;

struct?edge?{

????int?v;LL?c;int?ne;

????

}?e[M];

int?h[N],?idx?=?1;?//從2,3開始配對

int?d[N],?cur[N];

int?vis[N];

void?add(int?a,?int?b,?LL?c)?{

????e[++idx]?=?{b,?c,?h[a]};

????h[a]?=?idx;

}

bool?bfs()?{?//對點(diǎn)分層，找增廣路

????memset(d,?0,?sizeof?d);

????queue<int>q;

????q.push(S);

????d[S]?=?1;

????while?(q.size())?{

????????int?u?=?q.front();

????????q.pop();

????????for?(int?i?=?h[u];?i;?i?=?e[i].ne)?{

????????????int?v?=?e[i].v;

????????????if?(d[v]?==?0?&&?e[i].c)?{

????????????????d[v]?=?d[u]?+?1;

????????????????q.push(v);

????????????????if?(v?==?T)?return?true;

????????????}

????????}

????}

????return?false;

}

LL?dfs(int?u,?LL?mf)?{?//多路增廣

????if?(u?==?T)?return?mf;

????LL?sum?=?0;

????for?(int?i?=?cur[u];?i;?i?=?e[i].ne)?{

????????cur[u]?=?i;?//當(dāng)前弧優(yōu)化

????????int?v?=?e[i].v;

????????if?(d[v]?==?d[u]?+?1?&&?e[i].c)?{

????????????LL?f?=?dfs(v,?min(mf,?e[i].c));

????????????e[i].c?-=?f;

????????????e[i?^?1].c?+=?f;?//更新殘留網(wǎng)

????????????

????????????sum?+=?f;?//累加u的流出流量

????????????mf?-=?f;?//減少u的剩余流量

????????????if?(mf?==?0)?break;?//余量優(yōu)化

????????}

????}

????if?(sum?==?0)?d[u]?=?0;?//殘枝優(yōu)化

????return?sum;

}

LL?dinic()?{?//累加可行流

????LL?flow?=?0;

????while?(bfs())?{

????????memcpy(cur,?h,?sizeof?h);

????????flow?+=?dfs(S,?LNF);

????}

????return?flow;

}

int?main()?{

????int?a[N],?b[N];

????LL?c;

????int?n,?m;

????scanf("%d%d",?&n,?&m);

????S?=?1,?T?=?n;

????for?(int?i?=?1;?i?<=?m;?i++)?{

????????scanf("%d%d%lld",?&a[i],?&b[i],?&c);

????????add(a[i],?b[i],?c*mod+1?);

????????add(b[i],?a[i],?0);

????}

????LL??res?=?dinic();

????printf("%lld?",?res/mod);

????printf("%lld\n",??res%mod);

????//最小割的最少邊數(shù)

//????idx?=?1;

//????memset(h,?0,?sizeof?h);

//????for?(int?i?=?1;?i?<=?m;?i++)?{

//????????add(a[i],?b[i],?1);

//????????add(b[i],?a[i],?0);

//????}

//????printf("%d\n",??dinic());

????return?0;

}

```

因?yàn)槌艘砸粋€數(shù)可能爆int，直接加倍LL