RAHIA - Riyad And His Increasing Array
You are given an array of N integers.
In this array in a single operation, you can choose any i (where 1 <= i <= N) such that a[i]>0 and decrease a[i] by 1.
You have to determine is it possible to make the given array sorted (strictly increasing) after using some number of operations (possibly 0) described above.
Input
Input starts with an integer N (1 ≤ N ≤ 100000), number of elements of the array.
Next line contains N separated integers ai (1 ≤ ai ≤ 109).
Output
Print "YES" (without quotes), if you can make the array sorted (strictly increasing), otherwise print "NO".
Example
Input: 7 5 2 3 9 88 9 10 Output: YES
hide comments
mestu_paul:
2020-02-13 21:29:07
you can either decrease or not no problem |
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m_a_noman:
2020-02-13 18:52:52
cann't i skip any operation ???
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Added by: | Riyad |
Date: | 2020-02-06 |
Time limit: | 1s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | BASH C NCSHARP C++ 4.3.2 CPP CPP14 C99 FORTRAN JULIA PYTHON PYPY3 PYTHON3 RUBY |
Resource: | none |