🧩 Level Information

• Level Number：268
• Problem Statement：Since the diagram of black dots disappears one by one, add black dots to the center and left.
• Difficulty：Hard

🎯 Objective

Recognize the rule of the diagram (black dots disappearing one by one) and complete the pattern by adding black dots in the correct positions (center and left).

📝 Steps to Solve

1. First, observe each diagram (frame) in the problem and confirm how the number and position of black dots change.
2. Notice that the black dots decrease 'one by one' in each frame. In other words, it follows a pattern where one black dot disappears in each frame.
3. Track the order in which the black dots disappear (from which position they disappear) and predict 'where the black dots should remain' in the final frame.
4. Based on the rule, it can be inferred that in this pattern, the black dots should eventually remain (or appear) in the center and left positions.
5. In the provided blank diagram or among the options, add black dots to the center and left to complete the pattern.
6. Confirm that no dots are placed outside the center and left, and finalize your answer.

💡 Hints

• Try counting the number of black dots in each diagram. How many change each time?
• Consider that the black dots are not 'increasing' but 'disappearing'.
• By tracking the order in which the dots disappear, you will know which positions remain at the end.
• The black dots that should ultimately remain (or be placed) are in the center and left side.

🧠 Explanation & Key Points

This level is a visual pattern recognition shape puzzle. The key is to abstractly capture how the black dots drawn in the diagram change with each frame. Many players tend to simply look at the 'shape', but in this problem, the core is the 'change in the number and position of the black dots'. When looking at the given diagrams in order, it follows a rule where one black dot disappears with each frame. In other words, it's like a diagram version of an "arithmetic sequence that decreases by 1 at a time". However, not only does the number decrease, but there is also a specific sequence or rule about which position's dot disappears. Following that order, it can be inferred that ultimately, the black dots will remain/appear in the center and left. In this type of problem, thinking in the three stages of 'counting', 'tracking changes', and 'predicting the next step' can make it easier to understand. Especially important is the ability to extract only the regularity without being distracted by visual information.

🔍 Common Mistakes

• Only looking at the 'number' of black dots, ignoring changes in position, and choosing a completely different arrangement.
• Misunderstanding that the black dots are increasing and thinking it's an additive pattern (like 1, 2, 3, 4...).
• Only looking at the first and last diagrams without checking the intermediate changes, and placing black dots intuitively on the right or elsewhere.
• Trying to solve based solely on appearance without reading the statement 'one black dot disappears'.
• Only placing dots on one of the center or left, when both need to have dots.

🎉 Advice After Clearing

If you were able to solve this level, you're developing the ability to recognize rules from changes in diagrams. In the future, by observing what changes with a constant rule—such as number, position, orientation, color—you will be able to quickly solve similar types of puzzles. In the next level too, continue the habit of first searching for the 'pattern of change'.

🌟 Related Levels