32 lines
873 B
Java
32 lines
873 B
Java
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// Java program to find an element x in a sorted array using Exponential search.
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import java.util.Arrays;
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class ExponentialSearch
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{
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// Returns position of first occurrence of x in array
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static int exponentialSearch(int arr[], int n, int x)
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{
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// If x is present at first location itself
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if (arr[0] == x)
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return 0;
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// Find range for binary search by repeated doubling
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int i = 1;
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while (i < n && arr[i] <= x)
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i = i*2;
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// Call binary search for the found range.
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return Arrays.binarySearch(arr, i/2, Math.min(i, n-1), x);
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}
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// Driver code
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public static void main(String args[])
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{
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int arr[] = {2, 3, 4, 10, 40};
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int x = 10;
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int result = exponentialSearch(arr, arr.length, x);
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System.out.println((result < 0) ? "Element is not present in array" : "Element is present at index " + result);
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}
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}
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