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Signal Cascade

Statement

 Goal

This puzzle is about chain reactions and propagation.
Your task: You are given a grid containing numbers.
Each number represents the initial energy of a cell.

Every time a cell receives a signal, its energy increases by 1.
If the energy becomes greater than 9, the cell overloads:
° Its energy resets to 0.
° It sends the signal to all 8 neighboring cells (including horizontal, vertical and diagonal) except previously overloaded cells.

If several cells overload simultaneously, they may be processed in any order and should give the same result.

Your task is to simulate the cascade until no more overloads occur and output the final grid.
Input
Line 1: Two space-separated integers H and W, the height and width of the grid.
Next H lines: Each line contains W digits (0–9) representing one row of the grid.
Next line: Two space-separated integers R and C, the row and column indexes (0-based) of the starting cell receiving the initial signal.
Output
H lines: The final grid after the cascade.
Constraints
1 ≤ H, W ≤ 10
0 ≤ R < H
0 ≤ C < W
Example
Input
5 5
00000
08120
07930
06540
00000
2 2
Output
00000
09230
08040
07650
00000
Tags
Simulation, Grid
Difficulty
Easy
Test cases
Example Test
Input
5 5 00000 08120 07930 06540 00000 2 2
Output
00000 09230 08040 07650 00000
Example (Variation) Validator
Input
5 5 00000 04320 05910 06780 00000 2 2
Output
00000 05430 06020 07890 00000
Full Overload Test
Input
4 4 9999 9999 9999 9999 1 1
Output
0000 0000 0000 0000
Variation Full Overload Validator
Input
6 6 999999 999999 999999 999999 999999 999999 1 2
Output
000000 000000 000000 000000 000000 000000
Chain Reaction Test
Input
5 5 98989 89998 98989 89998 98989 2 2
Output
00000 00000 00000 00000 00000
Variation of Chain Reaction Validator
Input
4 4 9898 8998 9898 8998 3 2
Output
0000 0000 0000 0000
Diagonal Chain Test
Input
5 4 9090 0909 9090 0909 9090 0 2
Output
0302 3040 0403 3040 0302
Diagonal Chain (Variation) Validator
Input
5 4 9090 1909 9090 1909 9090 1 3
Output
0302 4040 0403 4040 0302
No Overload Test
Input
3 5 09009 34567 89012 0 0
Output
19009 34567 89012
Variation No Overload Validator
Input
3 5 09009 44567 99012 0 0
Output
19009 44567 99012
Large Calm Zone Test
Input
5 5 12345 67890 12345 67890 12345 4 4
Output
12345 67890 12345 67890 12346
Variation of the Large "Calm" Zone Validator
Input
5 5 12345 67890 12345 67890 11345 4 4
Output
12345 67890 12345 67890 11346
Random 1 Test
Input
8 8 56216539 28904942 76568587 24998868 63199871 03091281 12013239 13388564 5 3
Output
57327649 29038084 78900000 25000000 64500005 03205604 12124350 13388575
Random 1 (Variation) Validator
Input
8 8 10641459 25779568 77624688 08969999 04966991 42188859 44061161 33426767 4 6
Output
10652680 25780900 89969000 10000000 17000005 43400090 44184382 33426767
Random 2 Test
Input
10 10 4581127663 9799142986 9658750657 2982872404 9198961697 9025567179 5144016596 1082733427 1284893165 5929552222 4 2
Output
6904227663 0000452986 0000081657 6000003404 0600092697 0348777179 6244016596 1082733427 1284893165 5929552222
Random 2 (Variation) Validator
Input
10 10 9992141588 8318322342 9092643193 7959968768 0944961960 1038899284 9224590471 1789932648 5562208803 3152694957 7 4
Output
9992141588 9529322342 0405975293 0090000978 3089007070 2150000494 9249003571 1790063648 5574418803 3152694957
Solution language
Solution
Stub generator input
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