Geek is very fond of patterns. Once, his teacher gave him a pattern to solve. He gave Geek an integer n and asked him to build a pattern.
Help Geek to build the pattern.

Example 1:
Input: 5
Output:
ABCDE
ABCD
ABC
AB
A

Your Task:
You don't need to input anything. Complete the function printTriangle() which takes an integer n as the input parameter and print the pattern.
Constraints:
1<= N <= 20

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