Code Submission Evaluation System | Login |

**Task** | Statistics

Time limit: | 1.00 s | Memory limit: | 512 MB |

You are given all numbers between $1,2,\ldots,n$ except one. Your task is to find the missing number.

The first input line contains an integer $n$.

The second line contains $n-1$ numbers. Each number is distinct and between $1,2,\ldots,n$.

Print the missing number.

- $2 \le n \le 5 \cdot 10^5$

Input:

`5`

2 3 1 5

Output:

`4`