give array num contain n distinct number range 0 n return number range miss array Example 1input num 301output 2explanation n 3 3 number number range 03 2 miss number range appear numsexample 2input num 01output 2explanation n 2 2 number number range 02 2 miss number range appear numsexample 3input num 964235701output 8explanation n 9 9 number number range 09 8 miss number range appear num Constraintsn numslength1 n 1040 numsi nAll number num unique Follow could implement solution o1 extra space complexity on runtime complexity