#include <bits/stdc++.h>
#define ff first
#define ss second
#define endl '\n'
using namespace std;
const long long INF = (long long) 1e18;
const int mod = (int) 1e9+7;
const int MAXN = (int) 1e7+5;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
ll n;
bool pr[MAXN];
ll sum[MAXN];
int main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);cout.tie(nullptr);
#ifdef Local
freopen("C:/Users/Admin/Desktop/Yazilim/C/IO/int.txt","r",stdin);
freopen("C:/Users/Admin/Desktop/Yazilim/C/IO/out.txt","w",stdout);
#endif
int a, b;
cin>>a>>b;
int top = 0;
vector<int> prims;
prims.push_back(2);
for(int i = 3; i <= b; i += 2){
if(pr[i])
continue;
prims.push_back(i);
for(ll j = 1LL * i * i ; j <= b; j += i){
pr[j] = 1;
}
}
for(int i = 1; i <= b; i++)
sum[i] = 1;
for(int c: prims){
ll sm = 1;
for(ll x = c; x <= b; x *= c){
for(int j = x; j <= b; j += x){
sum[j] /= sm;
sum[j] *= (sm + x);
}
sm += x;
}
}
ll ans = 0;
for(int i = a; i <= b; i++){
ans += abs(sum[i] - 2*i);
}
cout<<ans<<endl;
#ifdef Local
cout<<endl<<fixed<<setprecision(2)<<1000.0 * clock() / CLOCKS_PER_SEC<< " milliseconds ";
#endif
}
Compilation message
savrsen.cpp: In function 'int main()':
savrsen.cpp:28:9: warning: unused variable 'top' [-Wunused-variable]
28 | int top = 0;
| ^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
364 KB |
Output is correct |
2 |
Correct |
1 ms |
364 KB |
Output is correct |
3 |
Correct |
4 ms |
1388 KB |
Output is correct |
4 |
Correct |
564 ms |
91096 KB |
Output is correct |
5 |
Correct |
548 ms |
91096 KB |
Output is correct |
6 |
Correct |
543 ms |
91096 KB |
Output is correct |
7 |
Correct |
515 ms |
84064 KB |
Output is correct |
8 |
Correct |
123 ms |
23656 KB |
Output is correct |