25 lines
679 B
JavaScript
25 lines
679 B
JavaScript
var isSorted = require('./isSorted');
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exports = function(arr, val) {
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var cmp =
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arguments.length > 2 && arguments[2] !== undefined
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? arguments[2]
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: isSorted.defComparator;
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var startIdx = 0;
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var endIdx = arr.length - 1;
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while (startIdx <= endIdx) {
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var middleIdx = startIdx + Math.floor((endIdx - startIdx) / 2);
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var middleVal = arr[middleIdx];
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if (cmp(middleVal, val) === 0) {
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return middleIdx;
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}
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if (cmp(middleVal, val) < 0) {
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startIdx = middleIdx + 1;
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} else {
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endIdx = middleIdx - 1;
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}
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}
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return -1;
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};
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module.exports = exports;
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