Two Sum (Sorted Array) in Java: Explanation & Practice

Find two numbers in a sorted array that add up to target

Problem summary

Given a sorted array and a target sum, find two numbers that add up to the target. Return their indices. Use the Two Pointer technique for O(n) solution.

Starter code

public class Main {
    public static void main(String[] args) {
        int[] nums = {2, 7, 11, 15};
        int target = 9;
        
        // Two pointer approach:
        // Start with left=0, right=n-1
        // If sum < target, move left++
        // If sum > target, move right--
        // Print: Indices: 0, 1
    }
}

Expected output and test cases

nums=[2,7,11,15], target=9
```
Indices: 0, 1
```
nums=[1,2,3,4], target=4
```
Indices: 0, 2
```
nums=[1,3,5,7], target=10
```
Indices: 1, 3
```

Hints

Use two pointers: left at start, right at end
If sum < target, we need a bigger number → move left pointer right
If sum > target, we need a smaller number → move right pointer left
Works because array is sorted!

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