链接描述#include<iostream>
#include <cmath>
#include <algorithm>
#include<cstdio>
#include <iomanip>
#include<iosfwd>
#include<ios>
#include<string>
using namespace std;
int main() {
int m,n,s=0;
cin>>m>>n;
for(int i=m;i<=n;i++){
if(i%2!=0){
s+=i;
}
}
cout<<s;
return 0;
}
