100% Acceptance!✅With Efficient Memory!✅ Very Easy To understand!✅
IntuitionApproachComplexity
Time complexity:O(n)✅

Space complexity:O(1)✅
Code
# Intuition
<!-- Describe your first thoughts on how to solve this problem. -->

# Approach
<!-- Describe your approach to solving the problem. -->

# Complexity
- Time complexity:$$O(n)$$✅
<!-- Add your time complexity here, e.g. $$O(n)$$ -->

- Space complexity:$$O(1)$$✅
<!-- Add your space complexity here, e.g. $$O(n)$$ -->

# Code
```cpp []
class Solution {
public:
    int smallestNumber(int n) {
        int sum=0;
        for(int b=0;b<=10;b++){
            sum+=pow(2,b);
            if(sum>=n)return sum;
        }
        return -1;
    }
};
```
['C++']