60 lines
1.4 KiB
C++
60 lines
1.4 KiB
C++
/*
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*
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* Created on: Jun 29, 2012
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* Author: Derek
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*
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* Updated on: June 17, 2020
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* Author: Llewellyn
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*
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* Example of the binary search algorithm
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*/
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#include <iostream>
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using namespace std;
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int binarySearch(int array[], int low, int high, int mid, int searchValue)
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{
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// if found return
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if(searchValue == array[mid]) {
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return mid;
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} else if (low <= high) {
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// get search again
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if (searchValue > array[mid]) {
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low = mid + 1;
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} else {
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high = mid - 1;
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}
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// get the mid point
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mid = (low + high) / 2;
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// recursion binary search
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return binarySearch(array, low, high, mid, searchValue);
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}
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return -1;
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}
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int main()
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{
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int a[] = {1, 5, 11, 14, 16, 18, 22, 24, 25, 28, 31, 35, 37, 39, 42, 44, 46, 48, 51, 55, 57, 59, 62, 63};
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int userValue;
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int low = 0;
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int high = sizeof(a) - 1;
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// get the mid point
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int mid = (low + high) / 2;
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cout << "Enter an integer: " << endl;
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cin >> userValue;
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int result = binarySearch(a, low, high, mid, userValue);
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if(result >= 0)
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{
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cout << "The number " << a[result] << " was found at the"
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" element with index " << result << endl;
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}
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else
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{
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cout << "The number " << userValue << " was not found. " << endl;
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}
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} |