HDU 3715 Go Deeper

Two-point answer + 2-SAT judgment

#include <cstdio>#include<cstring>#include<cmath>#include<vector>#include<algorithm>using namespacestd;Const intmaxn=8000+5;intm,n,t;intans;intL,r,mid;inta[10010],b[10010],c[10010];structtwosat{intN; Vector<int> g[maxn*2]; BOOLmark[maxn*2]; ints[maxn*2],c; BOOLDfsintx) {if(mark[x^1])return false; if(Mark[x])return true; MARK[X]=true; S[c++]=x;  for(intI=0; I<g[x].size (); i++)            if(!dfs (G[x][i]))return false; return true; }    voidInitintN) { This->n=N;  for(intI=0; i<n*2; i++) g[i].clear (); memset (Mark,0,sizeofmark); }    voidAdd_clause (intXinty) {g[x].push_back (y^1); G[y].push_back (x^1); }    BOOLsolve () { for(intI=0;i<2*n;i+=2)            if(!mark[i]&&!mark[i+1]) {c=0; if(!DFS (i)) {                     while(c>0) mark[s[--c]]=false; if(!dfs (i+1))return false; }            }        return true; }};intMain () {scanf ("%d",&T);  while(t--) {scanf ("%d%d",&n,&l);  for(intI=0; i<m;i++) scanf ("%d%d%d",&a[i],&b[i],&C[i]); L=0, r=M;  while(l<=R) {Mid= (l+r)/2; Twosat T;            T.init (N);  for(intI=0; i<mid;i++)            {                if(c[i]==2) {T.add_clause (2*a[i]+1,2*b[i]+1); }                Else if(c[i]==1) {T.add_clause (2*a[i]+1,2*B[i]); T.add_clause (2*a[i],2*b[i]+1); }                Else if(c[i]==0) {T.add_clause (2*a[i],2*B[i]); }            }            if(T.solve ()) {ans=Mid; L=mid+1; }            Elser=mid-1; } printf ("%d\n", ans); }    return 0;}

HDU 3715 Go Deeper