LESSON 168 OF 348 · LOOPS - CHALLENGES

Find Largest Number in Rust

Practice

Given a positive number S, find the largest number n such that the sum
1² + 2² + 3² + ... + n² is less than or equal to S.

For your information, n² = n * n

Example:

Input: S = 35

Output: 4

Explanation:
1² + 2² + 3² + 4² = 1 + 4 + 9 + 16 = 30
and 30 <= 35
if we add 5² we end up with 55, which exceeds 35
therefore 4 is the answer

Hints:

If we look at the explanation, a simple algorithm comes to mind:
Keep track of the totalSoFar and start iterating from 1 as long as adding number * number to totalSoFar is less than or equal to S.
You continue to add number * number to totalSoFar as long as you don't exceed S

STEP 1 OF 6

Guided

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