The 2019 China Collegiate Programming Contest Harbin Site A. Artful Paintings 差分约束模板
#includeusingnamespacestd;constintN=3010;constintINF=1e9;intdist[N];structnode{intu,v,cost;};structnode2{intl,r,k;};vectorE;vectorg1,g2;boolbf(intst,intn){for(inti=1;idist[u]+cost){dist[v]=dist[u]+cos