Kefa and First Steps - CodeForces | C++ Implementation
Kefa decided to make some money doing business on the Internet for exactly n days. He knows that on the i-th day (1≤i≤n) he makes ai money. Kefa loves progress, that’s why he wants to know the length of the maximum non-decreasing subsegment in sequence ai. Let us remind you that the subsegment of the sequence is its continuous fragment. A subsegment of numbers is called non-decreasing if all numbers in it follow in the non-decreasing order.
The second line contains n integers a1, a2, …, an
Print a single integer — the length of the maximum non-decreasing subsegment of sequence a.
Read full problem here : Kefa and First Steps
Let earnings
is an integer vector of size n
which stores amount earned on each day.
To find the length of the maximum increasing subsegment in a given sequence, you can use the following algorithm:
-
Initialize three integer variables:
current_earning
,final_count
, andlocal_count
.current_earning
should be set to the first element of theearnings
vector,final_count
should be set to 1, andlocal_count
should be set to 1.int current_earning = earnings[0]; // stores highest earning of non-decreasing subsegment int final_count = 1; // stores length of longest non-decreasing subsegment int local_count = 1; // stores length of current subsegment in process
``
-
Iterate over the
earnings
vector, starting at the second element (index 1). For each elementearnings[i]
, do the following:a. If
earnings[i] > current_earning
, incrementlocal_count
by 1 and setcurrent_earning
toearnings[i]
.b. If
earnings[i] <= current_earning
, setlocal_count
to 1 and setcurrent_earning
toearnings[i]
.c. If
local_count > final_count
, setfinal_count
tolocal_count
.for (int i = 1; i < n; i++) { if (earnings[i] > current_earning) { // if current earning is greater than previous earning, increment local count by 1 local_count++; current_earning = earnings[i]; } else { // if current earning is not greater than previous earning, reset local count to 1 local_count = 1; current_earning = earnings[i]; } // update final count if local count is greater than final count if (local_count > final_count) { final_count = local_count; } }
``
-
After the loop finishes, final_count will contain the length of the maximum increasing subsegment.
#include <iostream>
#include <vector>
int main()
{
int n;
std::cin >> n;
std::vector<int> earnings(n);
int current_earning = earnings[0]; // stores highest earning of non-decreasing subsegment
int final_count = 1; // stores length of longest non-decreasing subsegment
int local_count = 1; // stores length of current subsegment in process
for (int i = 1; i < n; i++)
{
if (earnings[i] > current_earning)
{
// if current earning is greater than previous earning, increment local count by 1
local_count++;
current_earning = earnings[i];
}
else
{
// if current earning is not greater than previous earning, reset local count to 1
local_count = 1;
current_earning = earnings[i];
}
// update final count if local count is greater than final count
if (local_count > final_count)
{
final_count = local_count;
}
}
std::cout << final_count << "\n";
}
Check out this on Github
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