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Visualize algorithms in real time, explore them step by step, or challenge yourself with a test.Choose a path to focus—or scroll down to preview all options.
Visualize the algorithm step-by-step with interactive animations in real time.
Read the full explanation, examples, and starter code at your own pace.
Drag and arrange the algorithm steps in the correct execution order.
🧠 Select Active to activate
Follow every state change, comparison, and transformation as the execution unfolds in real time.
📖 Select Passive to activate
You are given a grid with m x n dimensions, where each cell contains an arrow pointing to one of four directions:
(0, 0) and aim to reach the bottom-right corner (m-1, n-1) by following the arrows.1.Input: [[1,1,1,1],[2,2,2,2],[1,1,1,1],[2,2,2,2]]

3Explanation: Modify arrows in 3 cells to create a valid path from (0, 0) to (3, 3).
Input: [[1,1,3],[3,2,2],[1,1,4]]
Output: 0
Explanation: A valid path already exists without any modifications.
Input: [[1,2],[4,3]]
Output: 1
Explanation: Modify one cell's arrow to create a valid path.
1 <= m, n <= 1001 to 4.🎯 Select Challenge to activate
Drag and arrange the algorithm steps in the correct execution order instead of spending time typing code letter by letter.
The algorithm is divided into three logical parts. Carefully rearrange each section in the correct order to form a complete and valid solution.
Understand Below AlgorithmGreen text means the instruction is placed in the correct position.
Red text means the instruction is in the wrong position.
Instructions with the same background color indicate particular blocks start and end.
A tick mark means the instruction is correct and locked.
🔒 Locked steps cannot be moved. Only unlocked steps are draggable.
🔊 Enable sound for swap feedback and completion effects.