Error Monitoring System - IIT Roorkee Guwahati Goldman Sachs Online Assessment SDE Role

Problem

A monitoring system records the status of different services.

You are given a sequence of log entries. Each entry is represented as:

<service_name> <status>

where:

service_name is a string identifying the service.
status is either "success" or "error".

For every service, maintain the number of consecutive "error" logs since its last "success" or alert. Whenever a service accumulates 3 consecutive errors, an alert is triggered immediately, and its consecutive error count is reset to 0.

Your task is to determine the total number of alerts generated.

Input

N service1 status1 service2 status2 ... serviceN statusN

Output

Print a single integer — the total number of alerts generated.

Example 1:

Input:["2","service1 error","service1 error","service1 error","service1 success","service2 error","service2 error","service2 error"]

Output:2

Constraints:

1 ≤ N ≤ 2 × 10^5
1 ≤ |service_name| ≤ 20
The total length of all service names does not exceed 2 × 10^5

solution.cpp

Run code to see test results

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