LeetCode 솔루션

[12/13] 931. Minimum Falling Path Sum

학부유학생 쪽지보내기 메일보내기 자기소개 아이디로 검색 전체게시물 작성
작성일 2022.12.13 14:28

7,589 조회
1 댓글
0 추천
0 비추천
목록 게시글 쓰기

931. Minimum Falling Path Sum

Given an n x n array of integers matrix, return the minimum sum of any falling path through matrix.

A falling path starts at any element in the first row and chooses the element in the next row that is either directly below or diagonally left/right. Specifically, the next element from position (row, col) will be (row + 1, col - 1), (row + 1, col), or (row + 1, col + 1).

Example 1:

Input: matrix = [[2,1,3],[6,5,4],[7,8,9]]
Output: 13
Explanation: There are two falling paths with a minimum sum as shown.

Example 2:

Input: matrix = [[-19,57],[-40,-5]]
Output: -59
Explanation: The falling path with a minimum sum is shown.

Constraints:

n == matrix.length == matrix[i].length
1 <= n <= 100
-100 <= matrix[i][j] <= 100

Accepted

215.7K

Submissions

311.7K

Acceptance Rate

<span class="text-md font-medium" style="border: 0px solid; box-sizing: border-box; --tw-border-spacing-x:0; --tw-border-spacing-y:0; --tw-translate-x:0; --tw-translate-y:0; --tw-rotate:0; --tw-skew-x:0; --tw-skew-y:0; --tw-scale-x:1; --tw-scale-y:1; --tw-pan-x: ; --tw-pan-y: ; --tw-pinch-zoom: ; --tw-scroll-snap-strictness:proximity; --tw-ordinal: ; --tw-slashed-zero: ; --tw-numeric-figure: ; --tw-numeric-spacing: ; --tw-numeric-fraction: ; --tw-ring-inset: ; --tw-ring-offset-width:0px; --tw-ring-offset-color:#fff; --tw-ring-color:rgba(59,130,246,0.5); --tw-ring-offset-shadow:0 0 #0000; --tw-ring-shadow:0 0 #0000; --tw-shadow:0 0 #0000; --tw-shadow-colored:0 0 #0000; --tw-blur: ; --tw-brightness: ; --tw-contrast: ; --tw-grayscale: ;

#Amazon, #Visa

링크

https://leetcode.com/problems/minimum-falling-path-sum/description/ 996 회 연결

익명
작성일 2022.12.13 14:29

class Solution:
    def minFallingPathSum(self, matrix: List[List[int]]) -> int:
        dic = {}
        
        ROW, COL = len(matrix), len(matrix[0])
        directions = [(1,-1),(1,1),(1,0)]

        def dfs(r, c):
            if r == ROW-1:
                return matrix[r][c]
            if (r,c) in dic: return dic[(r,c)]
            

            min_path = float('inf')

            for rd, cd in directions:
                nr, nc = r + rd, c+cd
                if 0<=nr<ROW and 0<=nc<COL:
                    min_path = min(min_path, dfs(nr,nc))
            
            dic[(r,c)] = min_path + matrix[r][c]

            return min_path + matrix[r][c]


        return min(dfs(0,c) for c in range(COL))