50 lines
893 B
JavaScript
50 lines
893 B
JavaScript
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'use strict';
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import _ from '../utils';
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let arr = _.args.numbers();
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mergeSort(arr, 0, arr.length);
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_.log(arr.join(' '));
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function mergeSort(a, p, r) {
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if(r - p === 1) return;
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let q = Math.floor((r+p)/2);
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_.debug(`mergeSort(${[p, q, r]})`);
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mergeSort(a, p, q);
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mergeSort(a, q, r);
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merge(a, p, q, r);
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}
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function merge(a, p, q, r) {
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_.debug(`- merge(${[p, q, r]})`);
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let i = 0,
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j = 0;
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let left = a.slice(p, q),
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right = a.slice(q, r);
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_.debug(` - left = [${left}]`);
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_.debug(` - right = [${right}]`);
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left.push(Infinity);
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right.push(Infinity);
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for(let k = p; k < r; k++) {
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if(left[i] <= right[j]) {
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a[k] = left[i];
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_.debug(` - set a[${k}] = (left[${i}]=${left[i]})`);
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i++;
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} else {
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a[k] = right[j];
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_.debug(` - set a[${k}] = (right[${j}]=${right[j]})`);
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j++;
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}
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}
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_.debug(`a = [${a}]`);
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}
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