class Solution:
def minPathSum(self, grid: List[List[int]]) -> int:
# Step 1: Initialize the dp array with the same dimensions as the input grid.
m, n = len(grid), len(grid[0])
dp = [[0] * n for _ in range(m)]
# Step 2: Set the starting point.
dp[0][0] = grid[0][0]
# Step 3: Populate the first row and first column.
for i in range(1, m):
dp[i][0] = dp[i - 1][0] + grid[i][0]
for j in range(1, n):
dp[0][j] = dp[0][j - 1] + grid[0][j]
# Step 4: Iterate over the grid to populate the rest of the dp array.
for i in range(1, m):
for j in range(1, n):
dp[i][j] = grid[i][j] + min(dp[i - 1][j], dp[i][j - 1])
# Step 5: Return the value in the bottom-right corner.
return dp[-1][-1]