Dsa
Prefix Sum
Warm-up
Quiet Library Monitor
A library monitor records the noise level (in decibels) every minute for N minutes. A 'noise violation' is flagged if the average noise level from the start of the recording up to the current minute is strictly greater than a threshold T. Calculate the total number of noise violations that occurred during the N-minute period.
Input Format:
The first line contains two integers: N (minutes) and T (decibel threshold).
The second line contains N integers representing noise levels recorded each minute.
Output Format:
A single integer representing the total number of violations.
Example:
Input:
4 50
60 40 70 30
Output:
2
(Explanation: Min 1: Avg 60/1=60 (>50, Yes). Min 2: Avg 100/2=50 (>50, No). Min 3: Avg 170/3=56.6 (>50, Yes). Min 4: Avg 200/4=50 (>50, No).)
Key concepts
prefix_sumaverages
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