Binary Search on Array

Key Signals & Indicators

• Sorted array or list input
• Need to search elements in O(log n) time
• Finding target value, bounds, insertion index, boundary elements

// C++ Binary Search Template
#include <vector>

int binarySearch(const std::vector<int>& arr, int target) {
    int low = 0;
    int high = arr.size() - 1;
    
    while (low <= high) {
        int mid = low + (high - low) / 2; // Prevent overflow
        if (arr[mid] == target) {
            return mid;
        } else if (arr[mid] < target) {
            low = mid + 1;
        } else {
            high = mid - 1;
        }
    }
    return -1;
}