Given two strings str1 and str2, check if str2 can be formed from str1
Input : str1 = geekforgeeks, str2 = geeks Output : Yes Here, string2 can be formed from string1. Input : str1 = geekforgeeks, str2 = and Output : No Here string2 cannot be formed from string1. Input : str1 = geekforgeeks, str2 = geeeek Output : Yes Here string2 can be formed from string1 as string1 contains 'e' comes 4 times in string2 which is present in string1.
The idea is to count frequencies of characters of str1 in a count array. Then traverse str2 and decrease frequency of characters of str2 in the count array. If frequency of a characters becomes negative at any point, return false.
Below is the implementation of above approach :
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