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| #include<bitset> #include<cstdio> #include<cstring> #include<algorithm> using namespace std;
inline int rin(int &r){ int b=1,c=getchar();r=0; while(c<'0' || '9'<c) b=c=='-'?-1:b,c=getchar(); while('0'<=c && c<='9') r=(r<<1)+(r<<3)+(c^'0'),c=getchar(); return r*=b; } const int N=3e4+10; #define con(type) const type &
struct Dsu{ int fa[N<<1]; bool tag[N<<1]; inline int findFa(con(int)u){return fa[u]==u?u:fa[u]=findFa(fa[u]);} inline bool merge(int u,int v){ u=findFa(u),v=findFa(v); if(u==v){ if(tag[u]) return false; return tag[u]=true; } if(tag[u] && tag[v]) return false; fa[u]=v,tag[v]|=tag[u]; return true; } void init(con(int)n){ for(int i=1;i<=n;i++) fa[i]=i,tag[i]=false; } }ds; struct Graph{ int head[N<<1],to[N<<2],nxt[N<<2],len[N<<2],ncnt; Graph(){ncnt=1;} void addEdge(con(int)u,con(int)v,con(int)l){ int p=++ncnt,q=++ncnt; to[p]=v,nxt[p]=head[u],len[p]=l,head[u]=p; to[q]=u,nxt[q]=head[v],len[q]=l,head[v]=q; } inline int operator [](con(int)u){return head[u];} }gr;
int n,bonk,rcir,rlis,nval_bin,nval; int dep[N<<1],val_bin[N],val[N]; bitset<N*40> dp[2]; bool covered[N<<1];
bool searchDFS(con(int)u,con(int)las_edg){ bool oncir=false,fix_end=false; for(int it=gr[u];it;it=gr.nxt[it]){ int v=gr.to[it]; if((it>>1)==las_edg) continue; if(dep[v]){ if(dep[v]<dep[u]){ oncir=true; covered[v]=true; if(v>n) rcir+=gr.len[it]; else rcir-=gr.len[it]; } else fix_end=true; continue; } dep[v]=dep[u]+1; if(searchDFS(v,it>>1)){ oncir=true; if(v>n) rcir+=gr.len[it]; else rcir-=gr.len[it]; } else{ if(covered[v]){ covered[u]=true; if(u>n) rlis+=gr.len[it]; else rlis-=gr.len[it]; } else if(v>n) rlis+=gr.len[it]; else rlis-=gr.len[it]; } } return !fix_end && oncir; } int main(){ rin(n),rin(bonk); ds.init(n<<1); for(int i=1,li,ri,ki;i<=2*n;i++){ rin(li),ri=rin(ri)+n,rin(ki); if(!ds.merge(li,ri)){printf("NO\n");return 0;} gr.addEdge(li,ri,ki); } for(int i=1;i<=2*n;i++) if(ds.fa[i]==i && !ds.tag[i]){ printf("NO\n"); return 0; } int ini_val=0; for(int i=1;i<=2*n;i++) if(!dep[i]){ dep[i]=1; rlis=rcir=0,searchDFS(i,-1); if(rcir>0){ ini_val+=rlis-rcir; val_bin[++nval_bin]=rcir<<1; } else{ ini_val+=rlis+rcir; val_bin[++nval_bin]=(-rcir)<<1; } } sort(val_bin+1,val_bin+1+nval_bin); for(int i=1;i<=nval_bin;i++){ int ii=i,siz; while(ii<nval_bin && val_bin[ii+1]==val_bin[i]) ii++; siz=ii-i+1; for(int j=1;j<=siz;j<<=1){ val[++nval]=j*val_bin[i]; siz-=j; } if(siz) val[++nval]=siz*val_bin[i]; i=ii; } dp[0][0]=1; int I=1; for(int i=1;i<=nval;i++,I^=1) dp[I]=dp[!I]|(dp[!I]<<val[i]); for(int i=max(-bonk-ini_val,0);i<=min(bonk-ini_val,40*N-1);i++) if(dp[I][i]){ printf("YES\n"); return 0; } printf("NO\n"); return 0; }
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