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-# Programming strategy
-
+# Programming strategy ![Open University logo](oulogo_hor.png)
## Moving up a level
Data structures
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-.indexlink[[Index](index.html)]
+.indexlink[![Open University logo](oulogo_hor.png) [Index](index.html)]
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Do both with explicit iteration, then using only comprehensions.
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-
-# Solutions with explicit loops
```python
grid_nums = [int(n) for n in GRID_STRING.split()]
```
+---
+
+# Solutions with explicit loops
+
```python
g1 = []
for rowstart in range(0, ROWS * COLUMNS, COLUMNS):