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Diffstat (limited to 'deps/node/deps/icu-small/source/tools/toolutil/denseranges.cpp')
-rw-r--r-- | deps/node/deps/icu-small/source/tools/toolutil/denseranges.cpp | 160 |
1 files changed, 0 insertions, 160 deletions
diff --git a/deps/node/deps/icu-small/source/tools/toolutil/denseranges.cpp b/deps/node/deps/icu-small/source/tools/toolutil/denseranges.cpp deleted file mode 100644 index f5e52b1b..00000000 --- a/deps/node/deps/icu-small/source/tools/toolutil/denseranges.cpp +++ /dev/null @@ -1,160 +0,0 @@ -// © 2016 and later: Unicode, Inc. and others. -// License & terms of use: http://www.unicode.org/copyright.html -/* -******************************************************************************* -* Copyright (C) 2010, International Business Machines -* Corporation and others. All Rights Reserved. -******************************************************************************* -* file name: denseranges.cpp -* encoding: UTF-8 -* tab size: 8 (not used) -* indentation:4 -* -* created on: 2010sep25 -* created by: Markus W. Scherer -* -* Helper code for finding a small number of dense ranges. -*/ - -#include "unicode/utypes.h" -#include "denseranges.h" - -// Definitions in the anonymous namespace are invisible outside this file. -namespace { - -/** - * Collect up to 15 range gaps and sort them by ascending gap size. - */ -class LargestGaps { -public: - LargestGaps(int32_t max) : maxLength(max<=kCapacity ? max : kCapacity), length(0) {} - - void add(int32_t gapStart, int64_t gapLength) { - int32_t i=length; - while(i>0 && gapLength>gapLengths[i-1]) { - --i; - } - if(i<maxLength) { - // The new gap is now one of the maxLength largest. - // Insert the new gap, moving up smaller ones of the previous - // length largest. - int32_t j= length<maxLength ? length++ : maxLength-1; - while(j>i) { - gapStarts[j]=gapStarts[j-1]; - gapLengths[j]=gapLengths[j-1]; - --j; - } - gapStarts[i]=gapStart; - gapLengths[i]=gapLength; - } - } - - void truncate(int32_t newLength) { - if(newLength<length) { - length=newLength; - } - } - - int32_t count() const { return length; } - int32_t gapStart(int32_t i) const { return gapStarts[i]; } - int64_t gapLength(int32_t i) const { return gapLengths[i]; } - - int32_t firstAfter(int32_t value) const { - if(length==0) { - return -1; - } - int32_t minValue=0; - int32_t minIndex=-1; - for(int32_t i=0; i<length; ++i) { - if(value<gapStarts[i] && (minIndex<0 || gapStarts[i]<minValue)) { - minValue=gapStarts[i]; - minIndex=i; - } - } - return minIndex; - } - -private: - static const int32_t kCapacity=15; - - int32_t maxLength; - int32_t length; - int32_t gapStarts[kCapacity]; - int64_t gapLengths[kCapacity]; -}; - -} // namespace - -/** - * Does it make sense to write 1..capacity ranges? - * Returns 0 if not, otherwise the number of ranges. - * @param values Sorted array of signed-integer values. - * @param length Number of values. - * @param density Minimum average range density, in 256th. (0x100=100%=perfectly dense.) - * Should be 0x80..0x100, must be 1..0x100. - * @param ranges Output ranges array. - * @param capacity Maximum number of ranges. - * @return Minimum number of ranges (at most capacity) that have the desired density, - * or 0 if that density cannot be achieved. - */ -U_CAPI int32_t U_EXPORT2 -uprv_makeDenseRanges(const int32_t values[], int32_t length, - int32_t density, - int32_t ranges[][2], int32_t capacity) { - if(length<=2) { - return 0; - } - int32_t minValue=values[0]; - int32_t maxValue=values[length-1]; // Assume minValue<=maxValue. - // Use int64_t variables for intermediate-value precision and to avoid - // signed-int32_t overflow of maxValue-minValue. - int64_t maxLength=(int64_t)maxValue-(int64_t)minValue+1; - if(length>=(density*maxLength)/0x100) { - // Use one range. - ranges[0][0]=minValue; - ranges[0][1]=maxValue; - return 1; - } - if(length<=4) { - return 0; - } - // See if we can split [minValue, maxValue] into 2..capacity ranges, - // divided by the 1..(capacity-1) largest gaps. - LargestGaps gaps(capacity-1); - int32_t i; - int32_t expectedValue=minValue; - for(i=1; i<length; ++i) { - ++expectedValue; - int32_t actualValue=values[i]; - if(expectedValue!=actualValue) { - gaps.add(expectedValue, (int64_t)actualValue-(int64_t)expectedValue); - expectedValue=actualValue; - } - } - // We know gaps.count()>=1 because we have fewer values (length) than - // the length of the [minValue..maxValue] range (maxLength). - // (Otherwise we would have returned with the one range above.) - int32_t num; - for(i=0, num=2;; ++i, ++num) { - if(i>=gaps.count()) { - // The values are too sparse for capacity or fewer ranges - // of the requested density. - return 0; - } - maxLength-=gaps.gapLength(i); - if(length>num*2 && length>=(density*maxLength)/0x100) { - break; - } - } - // Use the num ranges with the num-1 largest gaps. - gaps.truncate(num-1); - ranges[0][0]=minValue; - for(i=0; i<=num-2; ++i) { - int32_t gapIndex=gaps.firstAfter(minValue); - int32_t gapStart=gaps.gapStart(gapIndex); - ranges[i][1]=gapStart-1; - ranges[i+1][0]=minValue=(int32_t)(gapStart+gaps.gapLength(gapIndex)); - } - ranges[num-1][1]=maxValue; - return num; -} |