#include using namespace std; typedef long long ll; typedef pair P; #define REP(i,n) for(ll i=0;i> H >> W; vector v; for(i=1;i<=H;i++){ if(i%2==1){ for(j=1;j<=W;j++){ if(j%4==1 || j%4==2) cout << "O"; else cout << "X"; } cout << endl; }else{ for(j=1;j<=W;j++){ if(j%4==1 || j%4==2) cout << "X"; else cout << "O"; } cout << endl; } } return 0; }