text: if sum is seen before , we found two pairs
code: if ( s . containsKey ( sum ) ) { System . out . print ( " ( " + s . get ( sum ) . first + " , ▁ " + s . get ( sum ) . second + " ) ▁ and ▁ ( " + x + " , ▁ " + y + " ) " + "NEW_LINE"); } else