Problem 13485

In this problem, you need to finish a string calculator.

The calculator has three string operators:

a + b: Concatenate the string b after the string a.
a - b: If string b has appeared in string a, delete the first appearance of b in a, otherwise the result is "error".
a / b: The number of occurrences of string b in string a.

Note: You are suggested to practice the usage of C++ string class (https://www.cplusplus.com/reference/string/string/).

function std::operator+: Concatenate strings (https://www.cplusplus.com/reference/string/string/operator+/)
public member function std::string::find: Find content in string (https://www.cplusplus.com/reference/string/string/find/)
public member function std::string::substr: Generate substring (https://www.cplusplus.com/reference/string/string/substr/)
etc.

The first line contains an integer N

The following N lines, each line contains two string a b.

testcases:

(6/6) 1 <= N <= 100, 1 <= |a|, |b| <= 100

The output contains N lines.

For each a b, output ((a - b)+b)/b

Sample Input 1:
4
abc e
abc b
abbbbc bb
abc 2

Sample Input 2:
3
nthu cs
nthucs h
nthuu u

Sample Output 1:
2
1
2
1

Sample Output 2:
1
1
2

13485.cpp

13485.h

13485 - String Calculator(class)