//😁😁循环累加就行了😁😁
#include <iostream>
#include <algorithm>
using namespace std;
int n, m, i;int main() {
	int sum = 0;
	cin >> n >> m;
	for (i = n;i <= m;i++)
		if (i % 2 == 1)
			sum += i;
	cout << sum << endl;
}

C++ :

#include<bits/stdc++.h>
using namespace std;
int n,m,d;
int main()
{
cin>>n>>m;
if(n%2==0)
	n=n+1;
for(int i=n;i<=m;i=i+2)
	{
	d=d+i;
	}
cout<<d;
}

Python :

# coding=utf-8
a,b=input().split()
c=int(a)
d=int(b)
if(c%2==0):
    c=c+1
if(d%2==0):
    d=d-1
e=(d-c)//2+1
print((c+d)*e//2)