﻿ Java - Get the first occurrence of an element of a array

# Java: Get the first occurrence of an element of a given array

## Java Basic: Exercise-119 with Solution

Write a Java program to get the first occurrence (Position starts from 0.) of an element of a given array.

Pictorial Presentation:

Sample Solution:

Java Code:

``````import java.util.Scanner;
public class Main {
public static void main(String[] args) {
// Declare an array of integers 'nums' and an integer 'target'
int nums[] = {2, 4, 6, 7, 8};
int target = 7;

// Initialize 'lower' to the start of the array and 'upper' to the end of the array
int lower = 0;
int upper = nums.length - 1;

// Initialize 'index' to -1; it will store the position of the 'target'
int index = -1;

// Perform a binary search to find the 'target' in the 'nums' array
while (lower <= upper) {
// Calculate the middle index 'mid'
int mid = (lower + upper) >> 1;

// Check if 'nums[mid]' is equal to the 'target'
if (nums[mid] == target) {
index = mid; // Set 'index' to the position of the 'target'
}

// Adjust 'lower' and 'upper' based on the comparison with 'target'
if (nums[mid] >= target) {
upper = mid - 1; // Move 'upper' to the left half
} else {
lower = mid + 1; // Move 'lower' to the right half
}
}

// Print the position of the 'target' in the array
System.out.print("Position of " + target + " is " + index);
}
}
```
```

Sample Output:

```Position of 7 is 3
```

Flowchart:

Java Code Editor:

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