Given a string S, check whether it can be converted into the string "hello" by deleting some characters from it.
Note : S can have both uppercase and lowercase letters.
Example 1:
Input:
S = "bbbbbxxhhelllllooudd"
Output: 1
Explanation: The string hello is marked
in bold: bbbbbxxhhelllllooudd
​Example 2:
Input:
S = "hlelo"
Output: 0
Explanation: It's impossible to convert
the given string into "hello".
Your Task:
You don't need to read input or print anything. Your task is to complete the function decode() which takes the string S as input and returns the true if the string can be converted to "hello", else return false.
Expected Time Complexity: O(|S|).
Expected Auxiliary Space: O(1).
Constraints:
1<=|S|<=10^{5}

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