Problem Brief

Command Frequency Counter

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You are given an array of commands. There are only three possible commands: cmd1, cmd2, and cmd3. Your task is to return an array of size 3 that contains the frequency of each command in the input array, in the order [frequency of cmd1, frequency of cmd2, frequency of cmd3].

Also, any element in the form of ![index] refers to the same command that was present at the position in the input array. Note that indexing starts from 1 (not 0).

Function Description

Complete the function commandFrequencyCounter in the editor.

commandFrequencyCounter has the following parameter:

String[] commands: an array of commands

Returns

int[]: an array of size 3 containing the frequency of each command

1Example 1

Input

commands = ["cmd1", "cmd2", "cmd3", "!1", "!2", "cmd3", "cmd1"]

Output

[3, 2, 2]

Explanation

At index 4 (!1), the command is the same as the command at index 1 (cmd1). At index 5 (!2), the command is the same as the command at index 2 (cmd2).