Given two strings s1 and s2, let us assume that while typing the strings there were some backspaces encountered which are represented by #. The task is to determine whether the resultant strings after processing the backspace character would be equal or not.
Input: s1= geee#e#ks, s2 = gee##eeks Output: True Explanation: Both the strings after processing the backspace character becomes "geeeeks". Hence, true. Input: s1 = equ#ual, s2 = ee#quaal# Output: False Explanation: String 1 after processing the backspace character becomes "equal" whereas string 2 is "eequaal". Hence, false.
To solve the problem mentioned above we have to observe that if the first character is ‘#’, that is there is certainly no character typed initially and hence we perform no operation. When we encounter any character other than ‘#’, then we add the character just after the current index. When we encounter a ‘#’, we move one index back, so instead of deleting the character, we just ignore it. Then finally compare the two strings by comparing each character from start to end.
Below is the implementation of the above approach:
Time Complexity: O(N)
Auxiliary Space: O(1)
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