#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}());
const ll mod=1000000007;
const ll mod2=998244353;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head
const int N=1010000;
int n,p,a[N],c[N];
ll pf[N];
int query(int x) {
int s=0;
for (;x;x-=x&-x) s+=c[x];
return s;
}
void modify(int x,int s) {
for (;x<N;x+=x&-x) c[x]+=s;
}
int main() {
scanf("%d",&n);
rep(i,1,n+1) scanf("%d",a+i),pf[i]=pf[i-1]+a[i];
scanf("%d",&p);
vector<ll> v;
/*(pf[i]-pf[j])/(i-j)>=p
pf[i]-pf[j]>=p*i-p*j
pf[i]-p*i>=pf[j]-p*j*/
rep(i,0,n+1) v.pb(pf[i]-(ll)p*i);
sort(all(v));
v.erase(unique(all(v)),v.end());
ll ans=0;
rep(i,0,n+1) {
int x=lower_bound(all(v),pf[i]-(ll)p*i)-v.begin()+1;
ans+=query(x);
modify(x,1);
}
printf("%lld",ans);
}
Compilation message
vudu.cpp: In function 'int main()':
vudu.cpp:38:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
38 | scanf("%d",&n);
| ~~~~~^~~~~~~~~
vudu.cpp:39:20: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
39 | rep(i,1,n+1) scanf("%d",a+i),pf[i]=pf[i-1]+a[i];
| ~~~~~^~~~~~~~~~
vudu.cpp:40:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
40 | scanf("%d",&p);
| ~~~~~^~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
588 KB |
Output is correct |
2 |
Correct |
2 ms |
492 KB |
Output is correct |
3 |
Correct |
2 ms |
588 KB |
Output is correct |
4 |
Correct |
304 ms |
32412 KB |
Output is correct |
5 |
Correct |
158 ms |
20364 KB |
Output is correct |
6 |
Correct |
247 ms |
28808 KB |
Output is correct |
7 |
Correct |
245 ms |
29900 KB |
Output is correct |
8 |
Correct |
220 ms |
25960 KB |
Output is correct |
9 |
Correct |
285 ms |
33488 KB |
Output is correct |
10 |
Correct |
246 ms |
29100 KB |
Output is correct |