// output
//0 1 3 6 10 15 21 28 36 45

int MAX=45;
int i=0;
int n=1;

while(i<=MAX) {
  print(i+" ");
  i=i+n;
  //n=n+1;
  n++;
}
println("");

for(i=0,n=1;i<=MAX; i=i+n,n=n+1){
  print(i+" ");
}
println(" ");
println("done");