Handle two digit numbers < 20
else if ( num [ i ] == '1' ) word += s + two_digits [ num [ i + 1 ] - '0' + 1 ] ; else { if ( num [ i ] != '0' ) word += s + tens_multiple [ num [ i ] - '0' ] . substr ( 0 , tens_multiple [ num [ i ] - '0' ] . length ( ) - 4 ) + " y ▁ " ; else word += s ; word += single_digits [ num [ i + 1 ] - '0' ] ; } i += 2 ; } if ( i == len ) { if ( word [ 0 ] == ' ▁ ' ) word . erase ( 0 , 1 ) ; } } return word ; }