B - Permutation Check
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B - Permutation Check
Score : $200$ points
Problem Statement
You are given a sequence of $N$ integers between $1$ and $N$ (inclusive): $A = (A_1, A_2, \dots, A_N)$.
Determine whether $A$ is a permutation of $(1, 2, \dots, N)$.
Constraints
- $1 \leq N \leq 10^3$
- $1 \leq A_i \leq N$
- All values in input are integers.
Input
Input is given from Standard Input in the following format:
Output
If $A$ is a permutation of $(1, 2, \dots, N)$, print Yes
; otherwise, print No
.
5
3 1 2 4 5
Yes
$(3, 1, 2, 4, 5)$ is a permutation of $(1, 2, 3, 4, 5)$, so we should print Yes
.
6
3 1 4 1 5 2
No
$(3, 1, 4, 1, 5, 2)$ is not a permutation of $(1, 2, 3, 4, 5, 6)$, so we should print No
.
3
1 2 3
Yes
1
1
Yes