Parnic
19f91dbc50
This is too common of an optimization to not have this readily accessible. And I kinda like how this worked out, too. Go is fun. Plus this both speeds up and "fixes" day 14's part 2 solution (it was always giving a correct answer, but mostly by chance based on how the input numbers worked out).
27 lines
773 B
Go
27 lines
773 B
Go
package utilities
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import (
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"math"
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)
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// Bisect takes a known-good low and known-bad high value as the bounds
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// to bisect, and a function to test each value for success or failure.
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// If the function succeeds, the value is adjusted toward the maximum,
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// and if the function fails, the value is adjusted toward the minimum.
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// The final value is returned when the difference between the success
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// and the failure is less than or equal to the acceptance threshold
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// (usually 1, for integers).
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func Bisect[T Number](low, high, threshold T, tryFunc func(val T) bool) T {
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for T(math.Abs(float64(high-low))) > threshold {
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currVal := low + ((high - low) / 2)
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success := tryFunc(currVal)
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if success {
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low = currVal
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} else {
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high = currVal
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}
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}
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return low
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}
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