45 lines
1.2 KiB
Java
45 lines
1.2 KiB
Java
package Maths;
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public class FindMinRecursion {
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public static void main(String[] args) {
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int[] array = {2, 4, 9, -7, 19, 94, 5};
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int low = 0;
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int high = array.length - 1;
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assert min(array, low, high) == -7;
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assert min(array, array.length) == -7;
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}
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/**
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* Get min of array using divide and conquer algorithm
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*
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* @param array contains elements
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* @param low the index of the first element
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* @param high the index of the last element
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* @return min of {@code array}
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*/
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public static int min(int[] array, int low, int high) {
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if (low == high) {
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return array[low]; //or array[high]
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}
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int mid = (low + high) >>> 1;
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int leftMin = min(array, low, mid); //get min in [low, mid]
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int rightMin = min(array, mid + 1, high); //get min in [mid+1, high]
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return Math.min(leftMin, rightMin);
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}
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/**
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* Get min of array using recursion algorithm
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*
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* @param array contains elements
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* @param len length of given array
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* @return min value of {@code array}
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*/
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public static int min(int[] array, int len) {
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return len == 1 ? array[0] : Math.min(min(array, len - 1), array[len - 1]);
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}
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}
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