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binary_search.js
1// Finds target in a sorted array
2function binarySearch(arr, target) {
3 let left = 0,
4 right = arr.length - 1;
5 while (left <= right) {
6 let mid = Math.floor((left + right) / 2);
7 if (arr[mid] === target)
8 return mid;
9 else if (arr[mid] < target)
10 left = mid + 1;
11 else
12 right = mid - 1;
13 }
14 return -1;
15}
Time complexity
O(log n)
Halves search space each iteration
Space complexity
O(1)
Constant - no extra allocations
Improvement suggestions
Use mid = left + Math.floor((right - left) / 2) to avoid integer overflow on large arrays.
Add an early guard when array is empty or target is out of range.
Recursive variant improves readability, but raises stack usage to O(log n).
Code converter
Python to JavaScript reveal
Drag the slider to compare a Python snippet with its JavaScript output and inspect how each line translates.
Focus
Syntax translation
Use case
Learn language patterns
converter.ts • preview
// JavaScript
function greet(name) {
const msg = `Hello, ${name}!`;
console.log(msg);
return msg;
}
greet("world");# Python
def greet(name):
msg = f"Hello, {name}!"
print(msg)
return msg
greet("world")Converter statusready to compare— python ↔ javascript
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