Greedy and Solve reversely

Lots of problems will be much easier if solve them reversely. Here is one example from leetcode.

936. Stamping The Sequence

The solution is given here:

[Python] Greedy and DFS - LeetCode Discuss

One python code is given here:

Solve reversely

844. Backspace String Compare

Backspace String Compare - LeetCode

def backspaceCompare(self, S, T):
        i, j = len(S) - 1, len(T) - 1
        backS = backT = 0
        while True:
            while i >= 0 and (backS or S[i] == '#'):
                backS += 1 if S[i] == '#' else -1
                i -= 1
            while j >= 0 and (backT or T[j] == '#'):
                backT += 1 if T[j] == '#' else -1
                j -= 1
            if not (i >= 0 and j >= 0 and S[i] == T[j]):
                return i == j == -1
            i, j = i - 1, j - 1

Thanks for reading.