SDE Path

Smallest Missing Positive

Medium

Smallest Missing Positive

Find the smallest positive integer absent from an array.

Input format

The first line has one integer N. The second line has N space-separated integers.

Output format

Print the smallest positive integer (1, 2, 3, ...) that does not appear in the array.

Constraints

  • Values fit in a 64-bit signed integer
  • Trailing whitespace and a trailing newline are ignored by the judge

Read from stdin, write to stdout. Sample cases below show the exact format.

Sample cases

Example 1
Input
3
1 2 0
Expected output
3
Example 2
Input
4
3 4 -1 1
Expected output
2