Missing Integer

Unit 3 Session 2 (Click for link to problem statements)

U-nderstand

Understand what the interviewer is asking for by using test cases and questions about the problem.

• Will there be more than one missing integer?
  • No.
• Will the list always start at 1?
  • Not necessarily! Start counting from first element in the list.
• What if there is no missing integer?
  • In that case, you'll return the number after the final element in the list.

P-lan

Plan the solution with appropriate visualizations and pseudocode.

General Idea: Compare each value to its index -- if it's not equal to the index + 1, we found the missing number.

1) Create an index variable at 0
2) While index is valid for our list
  a) Is list[index] same as index + 1?
    i) If yes, move on to next index
   ii) If not, index+1 is our missing value
3) 

⚠️ Common Mistakes

I-mplement