recursive call
checkIfPossibleRec ( x + a , a , b , isPossible , n ) ; checkIfPossibleRec ( x + b , a , b , isPossible , n ) ; } bool checkPossible ( int n , int a , int b ) { bool isPossible [ n + 1 ] = { false } ; checkIfPossibleRec ( 0 , a , b , isPossible , n ) ; return isPossible [ n ] ; }