feat: Add solution for 3548. Equal Sum Grid Partition I

[iamAntimPal]

Problem

3548. Equal Sum Grid Partition I
Difficulty: Medium
LeetCode Link

You are given an m x n matrix grid of positive integers. Your task is to determine if it is possible to make either one horizontal or one vertical cut on the grid such that:

• Each of the two resulting sections formed by the cut is non-empty.
• The sum of the elements in both sections is equal.

Return true if such a partition exists; otherwise return false.

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Solution

This solution checks all valid horizontal and vertical cuts:

1. Calculate the total sum of the grid.
2. Try all possible horizontal cuts by summing rows from top to bottom and checking if the prefix equals half of the total.
3. Try all possible vertical cuts by summing columns from left to right and checking the same.

Time Complexity: O(m * n)
Space Complexity: O(n) (for storing column sums)

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Language

• Python 3

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Code

class Solution:
    def canPartitionGrid(self, grid: List[List[int]]) -> bool:
        m, n = len(grid), len(grid[0])
        total_sum = sum(sum(row) for row in grid)

        # Try horizontal cut
        row_sum = 0
        for i in range(m - 1):
            row_sum += sum(grid[i])
            if row_sum * 2 == total_sum:
                return True

        # Try vertical cut
        col_sums = [0] * n
        for i in range(m):
            for j in range(n):
                col_sums[j] += grid[i][j]

        col_sum = 0
        for j in range(n - 1):
            col_sum += col_sums[j]
            if col_sum * 2 == total_sum:
                return True

        return False

[idoocs]

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🤭 Thank you for your contribution. Please check if your changes comply with the following project specifications.

1. Formatting

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• Add or modify solutions: feat: add/update solution(s) to lc problem(s): No.xxxx
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In addition, the coding style (such as the naming of variables and functions) should be as consistent as possible with the existing code in the project.