Count number of triplets in an array having sum in the range [ a , b ] | Function to count triplets ; Initialize result ; Fix the first element as A [ i ] ; Fix the second element as A [ j ] ; Now look for the third number ; Driver code
def countTriplets ( arr , n , a , b ) : NEW_LINE INDENT ans = 0 NEW_LINE for i in range ( 0 , n - 2 ) : NEW_LINE INDENT for j in range ( i + 1 , n - 1 ) : NEW_LINE INDENT for k in range ( j + 1 , n ) : NEW_LINE INDENT if ( ( arr [ i ] + arr [ j ] + arr [ k ] >= a ) and ( arr [ i ] + arr [ j ] + arr [ k ] <= b ) ) : NEW_LINE INDENT ans += 1 NEW_LINE DEDENT DEDENT DEDENT DEDENT return ans NEW_LINE DEDENT if __name__ == " _ _ main _ _ " : NEW_LINE INDENT arr = [ 2 , 7 , 5 , 3 , 8 , 4 , 1 , 9 ] NEW_LINE n = len ( arr ) NEW_LINE a = 8 ; b = 16 NEW_LINE print ( countTriplets ( arr , n , a , b ) ) NEW_LINE DEDENT