1646. Get Maximum in Generated Array
2 min readFeb 25, 2021
You are given an integer n
. An array nums
of length n + 1
is generated in the following way:
nums[0] = 0
nums[1] = 1
nums[2 * i] = nums[i]
when2 <= 2 * i <= n
nums[2 * i + 1] = nums[i] + nums[i + 1]
when2 <= 2 * i + 1 <= n
Return the maximum integer in the array nums
.
Example 1:
Input: n = 7
Output: 3
Explanation: According to the given rules:
nums[0] = 0
nums[1] = 1
nums[(1 * 2) = 2] = nums[1] = 1
nums[(1 * 2) + 1 = 3] = nums[1] + nums[2] = 1 + 1 = 2
nums[(2 * 2) = 4] = nums[2] = 1
nums[(2 * 2) + 1 = 5] = nums[2] + nums[3] = 1 + 2 = 3
nums[(3 * 2) = 6] = nums[3] = 2
nums[(3 * 2) + 1 = 7] = nums[3] + nums[4] = 2 + 1 = 3
Hence, nums = [0,1,1,2,1,3,2,3], and the maximum is 3.
Example 2:
Input: n = 2
Output: 1
Explanation: According to the given rules, the maximum between nums[0], nums[1], and nums[2] is 1.
Example 3:
Input: n = 3
Output: 2
Explanation: According to the given rules, the maximum between nums[0], nums[1], nums[2], and nums[3] is 2.
Constraints:
0 <= n <= 100
My Approach to given question : -
int getMaximumGenerated(int n) {
if(n == 0) {
return 0;
}
vector<int> v;
v.push_back(0); // v[0] first element
v.push_back(1); // v[1] second element
int MAX = 1; // since 1 is max of v[0] & v[1]
for(int i = 2; i <= n; i++) { // iterate from 2 to n as total n+1 elements are to push
if(i%2 == 0) { // If i is divisible by 2 then val = v[i/2]
int val = v[i/2];
v.push_back(val);
MAX = max(v[i], MAX); // update the max value
}
else {
int val = v[i/2]+v[(i/2)+1]; // if i is not divided by 2 then push v[i/2] + v[(i/2)+1]
v.push_back(val);
MAX = max(v[i], MAX); // update max value
}
}
return MAX;
}