| 1 | n/a | """Bisection algorithms.""" |
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| 2 | n/a | |
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| 3 | n/a | def insort_right(a, x, lo=0, hi=None): |
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| 4 | n/a | """Insert item x in list a, and keep it sorted assuming a is sorted. |
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| 5 | n/a | |
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| 6 | n/a | If x is already in a, insert it to the right of the rightmost x. |
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| 7 | n/a | |
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| 8 | n/a | Optional args lo (default 0) and hi (default len(a)) bound the |
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| 9 | n/a | slice of a to be searched. |
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| 10 | n/a | """ |
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| 11 | n/a | |
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| 12 | n/a | if lo < 0: |
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| 13 | n/a | raise ValueError('lo must be non-negative') |
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| 14 | n/a | if hi is None: |
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| 15 | n/a | hi = len(a) |
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| 16 | n/a | while lo < hi: |
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| 17 | n/a | mid = (lo+hi)//2 |
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| 18 | n/a | if x < a[mid]: hi = mid |
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| 19 | n/a | else: lo = mid+1 |
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| 20 | n/a | a.insert(lo, x) |
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| 21 | n/a | |
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| 22 | n/a | def bisect_right(a, x, lo=0, hi=None): |
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| 23 | n/a | """Return the index where to insert item x in list a, assuming a is sorted. |
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| 24 | n/a | |
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| 25 | n/a | The return value i is such that all e in a[:i] have e <= x, and all e in |
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| 26 | n/a | a[i:] have e > x. So if x already appears in the list, a.insert(x) will |
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| 27 | n/a | insert just after the rightmost x already there. |
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| 28 | n/a | |
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| 29 | n/a | Optional args lo (default 0) and hi (default len(a)) bound the |
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| 30 | n/a | slice of a to be searched. |
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| 31 | n/a | """ |
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| 32 | n/a | |
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| 33 | n/a | if lo < 0: |
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| 34 | n/a | raise ValueError('lo must be non-negative') |
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| 35 | n/a | if hi is None: |
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| 36 | n/a | hi = len(a) |
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| 37 | n/a | while lo < hi: |
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| 38 | n/a | mid = (lo+hi)//2 |
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| 39 | n/a | if x < a[mid]: hi = mid |
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| 40 | n/a | else: lo = mid+1 |
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| 41 | n/a | return lo |
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| 42 | n/a | |
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| 43 | n/a | def insort_left(a, x, lo=0, hi=None): |
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| 44 | n/a | """Insert item x in list a, and keep it sorted assuming a is sorted. |
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| 45 | n/a | |
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| 46 | n/a | If x is already in a, insert it to the left of the leftmost x. |
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| 47 | n/a | |
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| 48 | n/a | Optional args lo (default 0) and hi (default len(a)) bound the |
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| 49 | n/a | slice of a to be searched. |
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| 50 | n/a | """ |
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| 51 | n/a | |
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| 52 | n/a | if lo < 0: |
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| 53 | n/a | raise ValueError('lo must be non-negative') |
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| 54 | n/a | if hi is None: |
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| 55 | n/a | hi = len(a) |
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| 56 | n/a | while lo < hi: |
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| 57 | n/a | mid = (lo+hi)//2 |
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| 58 | n/a | if a[mid] < x: lo = mid+1 |
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| 59 | n/a | else: hi = mid |
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| 60 | n/a | a.insert(lo, x) |
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| 61 | n/a | |
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| 62 | n/a | |
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| 63 | n/a | def bisect_left(a, x, lo=0, hi=None): |
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| 64 | n/a | """Return the index where to insert item x in list a, assuming a is sorted. |
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| 65 | n/a | |
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| 66 | n/a | The return value i is such that all e in a[:i] have e < x, and all e in |
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| 67 | n/a | a[i:] have e >= x. So if x already appears in the list, a.insert(x) will |
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| 68 | n/a | insert just before the leftmost x already there. |
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| 69 | n/a | |
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| 70 | n/a | Optional args lo (default 0) and hi (default len(a)) bound the |
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| 71 | n/a | slice of a to be searched. |
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| 72 | n/a | """ |
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| 73 | n/a | |
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| 74 | n/a | if lo < 0: |
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| 75 | n/a | raise ValueError('lo must be non-negative') |
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| 76 | n/a | if hi is None: |
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| 77 | n/a | hi = len(a) |
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| 78 | n/a | while lo < hi: |
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| 79 | n/a | mid = (lo+hi)//2 |
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| 80 | n/a | if a[mid] < x: lo = mid+1 |
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| 81 | n/a | else: hi = mid |
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| 82 | n/a | return lo |
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| 83 | n/a | |
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| 84 | n/a | # Overwrite above definitions with a fast C implementation |
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| 85 | n/a | try: |
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| 86 | n/a | from _bisect import * |
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| 87 | n/a | except ImportError: |
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| 88 | n/a | pass |
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| 89 | n/a | |
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| 90 | n/a | # Create aliases |
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| 91 | n/a | bisect = bisect_right |
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| 92 | n/a | insort = insort_right |
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