0_0_14094194_18792.cpp:11:34: error: redefinition of 'int k' int vis[2000000],tp,flag,t,k,i,j,k; ^ 0_0_14094194_18792.cpp:11:28: note: 'int k' previously declared here int vis[2000000],tp,flag,t,k,i,j,k; ^