Minimum Path Sum in Grid in DSA Typescript - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to initialize the first cell of the dp array with the grid's first cell value.

DSA Typescript

const m = grid.length;
const n = grid[0].length;
const dp: number[][] = Array.from({ length: m }, () => Array(n).fill(0));
dp[0][0] = grid[1][0][0];

Drag options to blanks, or click blank then click option'

A<

B(

C{

D[

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses or curly braces instead of square brackets for indexing.

We use square brackets to access elements in a 2D array. So grid[0][0] accesses the first cell.

2fill in blank

medium

Complete the code to fill the first row of the dp array by accumulating sums from the left.

DSA Typescript

for (let j = 1; j < n; j++) {
  dp[0][j] = dp[0][j - 1] [1] grid[0][j];
}

Drag options to blanks, or click blank then click option'

A+

B-

C*

D/

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction or multiplication instead of addition.

We add the previous sum dp[0][j - 1] to the current grid value to accumulate the path sum.

3fill in blank

hard

Fix the error in the code to correctly fill the first column of the dp array by accumulating sums from above.

DSA Typescript

for (let i = 1; i < m; i++) {
  dp[i][0] = dp[i - 1][0] [1] grid[i][0];
}

Drag options to blanks, or click blank then click option'

A+

B-

C*

D/

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction or division instead of addition.

We add the value from the cell above dp[i - 1][0] to the current grid value to accumulate the path sum.

4fill in blank

hard

Fill both blanks to compute the minimum path sum for each cell by choosing the smaller sum from top or left.

DSA Typescript

for (let i = 1; i < m; i++) {
  for (let j = 1; j < n; j++) {
    dp[i][j] = grid[i][j] + Math.[1](dp[i - 1][j], dp[i][[2] - 1]);
  }
}

Drag options to blanks, or click blank then click option'

Amin

Bmax

Cabs

Dround

Attempts:

3 left

💡 Hint

Common Mistakes

Using Math.max instead of Math.min.

Using wrong index for left neighbor.

We use Math.min to pick the smaller sum from the top or left cell. The second blank is 'j' to access the left cell dp[i][j - 1].

5fill in blank

hard

Fill all three blanks to return the minimum path sum from top-left to bottom-right of the grid.

DSA Typescript

function minPathSum(grid: number[][]): number {
  const m = grid.length;
  const n = grid[0].length;
  const dp: number[][] = Array.from({ length: m }, () => Array(n).fill(0));
  dp[0][0] = grid[0][0];
  for (let i = 1; i < m; i++) {
    dp[i][0] = dp[i - 1][0] + grid[i][0];
  }
  for (let j = 1; j < n; j++) {
    dp[0][j] = dp[0][j - 1] + grid[0][j];
  }
  for (let i = 1; i < m; i++) {
    for (let j = 1; j < n; j++) {
      dp[i][j] = grid[i][j] + Math.min(dp[i - 1][j], dp[i][j - 1]);
    }
  }
  return dp[1][2][3];
}

Drag options to blanks, or click blank then click option'

A[m - 1]

B[n - 1]

C[m - 1][n - 1]

D[0][0]

Attempts:

3 left

💡 Hint

Common Mistakes

Returning dp[m - 1] or dp[n - 1] alone instead of dp[m - 1][n - 1].

We return dp[m - 1][n - 1], the bottom-right cell, which holds the minimum path sum.