Counting Character Occurrence Ignoring Case

Problem Description

Given a string s and a character c, count the number of times the character appears in the string, ignoring case differences. In other words, uppercase and lowercase versions of a letter are treated as the same.

Formally, if the input string is s and the character is c, then the answer is given by: $$\text{count} = \sum_{i=1}^{|s|} \mathbf{1}\{\text{tolower}(s_i)=\text{tolower}(c)\},$$ where \(\mathbf{1}\{\cdot\}\) is the indicator function.

Your program should read the input from standard input (stdin) and output the result to standard output (stdout).

inputFormat

The input consists of two lines:

• The first line is a non-empty string s.
• The second line is a single character c whose occurrences you need to count in s, ignoring case.

outputFormat

Output a single integer representing the count of occurrences of c in s in a case-insensitive manner.

Hello World
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