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104 lines
2.8 KiB
104 lines
2.8 KiB
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/* |
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* Licensed to the Apache Software Foundation (ASF) under one |
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* or more contributor license agreements. See the NOTICE file |
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* distributed with this work for additional information |
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* regarding copyright ownership. The ASF licenses this file |
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* to you under the Apache License, Version 2.0 (the |
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* "License"); you may not use this file except in compliance |
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* with the License. You may obtain a copy of the License at |
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* |
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* http://www.apache.org/licenses/LICENSE-2.0 |
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* |
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* Unless required by applicable law or agreed to in writing, |
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* software distributed under the License is distributed on an |
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* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
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* KIND, either express or implied. See the License for the |
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* specific language governing permissions and limitations |
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* under the License. |
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*/ |
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/** |
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* AUTO-GENERATED FILE. DO NOT MODIFY. |
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*/ |
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/* |
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* Licensed to the Apache Software Foundation (ASF) under one |
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* or more contributor license agreements. See the NOTICE file |
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* distributed with this work for additional information |
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* regarding copyright ownership. The ASF licenses this file |
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* to you under the Apache License, Version 2.0 (the |
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* "License"); you may not use this file except in compliance |
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* with the License. You may obtain a copy of the License at |
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* |
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* http://www.apache.org/licenses/LICENSE-2.0 |
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* |
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* Unless required by applicable law or agreed to in writing, |
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* software distributed under the License is distributed on an |
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* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
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* KIND, either express or implied. See the License for the |
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* specific language governing permissions and limitations |
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* under the License. |
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*/ |
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function defaultCompareFunc(a, b) { |
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return a - b; |
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} |
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function swapElement(arr, idx0, idx1) { |
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var tmp = arr[idx0]; |
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arr[idx0] = arr[idx1]; |
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arr[idx1] = tmp; |
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} |
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function select(arr, left, right, nth, compareFunc) { |
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var pivotIdx = left; |
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var pivotValue; |
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while (right > left) { |
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pivotIdx = Math.round((right + left) / 2); |
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pivotValue = arr[pivotIdx]; // Swap pivot to the end |
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swapElement(arr, pivotIdx, right); |
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pivotIdx = left; |
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for (var i = left; i <= right - 1; i++) { |
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if (compareFunc(pivotValue, arr[i]) >= 0) { |
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swapElement(arr, i, pivotIdx); |
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pivotIdx++; |
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} |
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} |
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swapElement(arr, right, pivotIdx); |
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if (pivotIdx === nth) { |
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return pivotIdx; |
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} else if (pivotIdx < nth) { |
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left = pivotIdx + 1; |
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} else { |
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right = pivotIdx - 1; |
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} |
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} // Left == right |
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return left; |
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} |
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function quickSelect(arr, left, right, nth, compareFunc) { |
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if (arguments.length <= 3) { |
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nth = left; |
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if (arguments.length === 2) { |
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compareFunc = defaultCompareFunc; |
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} else { |
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compareFunc = right; |
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} |
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left = 0; |
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right = arr.length - 1; |
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} |
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return select(arr, left, right, nth, compareFunc); |
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} |
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export default quickSelect; |