40 lines
649 B
Go
40 lines
649 B
Go
package main
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func clamp(int v, int m) int {
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if v < 0 {
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return 0
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}
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if v > m {
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return m
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}
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return v
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}
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type Cursor struct {
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row int
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col int
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}
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func (c Cursor) clamp(dr, dc, maxRow, maxCol int) Cursor {
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return Cursor{
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row: clamp(c.row+dr, maxRow),
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col: clamp(c.col+dc, maxCol),
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}
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}
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func (c Cursor) left(maxRow, maxCol int) Cursor {
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return c.clamp(0, -1, maxRow, maxCol)
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}
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func (c Cursor) right(maxRow, maxCol) Cursor {
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return c.clamp(0, 1, maxRow, maxCol)
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}
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func (c Cursor) up(maxRow, maxCol) Cursor {
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return c.clamp(-1, 0, maxRow, maxCol)
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}
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func (c Cursor) down(maxRow, maxCol) Cursor {
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return c.clamp(1, 0, maxRow, maxCol)
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}
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