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QOJ
| ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
|---|---|---|---|---|---|---|---|---|---|
| #352181 | #7962. 前缀和 | wuzhichen | AC ✓ | 0ms | 3900kb | C++14 | 563b | 2024-03-12 22:47:26 | 2024-03-12 22:47:27 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
const double eps=1e-8;
int n,l,r;double p,ans=0.0;
int fact(int n){
int ans=1;
for(int i=1;i<=n;i++)ans*=i;
return ans;
}
double comb(int n,int m){
if(m>n)return 0.0;
return fact(n)*1.0/(fact(m)*1.0*fact(n-m));
}
int main(){
scanf("%d %lf %d %d",&n,&p,&l,&r);
ans=(r-l+1)*1.0*p;
/*
for(int i=1;i<=n;i++)
for(int j=l;j<=r;j++)
if(j>=i)ans+=1.0*pow(p,i)*pow(1.0-p,j-i);
*/
printf("%.8lf",ans);
return 0;
}
/*
3 0.5 1 2
1 0.5 1 2
1000000000 0.592692 495948205 808386938
*/
詳細信息
Test #1:
score: 100
Accepted
time: 0ms
memory: 3884kb
input:
3 0.5 1 2
output:
1.00000000
result:
ok found '1.0000000', expected '1.0000000', error '0.0000000'
Test #2:
score: 0
Accepted
time: 0ms
memory: 3852kb
input:
1 0.529148 1 1
output:
0.52914800
result:
ok found '0.5291480', expected '0.5291480', error '0.0000000'
Test #3:
score: 0
Accepted
time: 0ms
memory: 3868kb
input:
1000000000 0.592692 495948205 808386938
output:
185179938.13192800
result:
ok found '185179938.1319280', expected '185179938.1320000', error '0.0000000'
Test #4:
score: 0
Accepted
time: 0ms
memory: 3852kb
input:
362633210 0.587463 165288121 324679823
output:
93636728.01948899
result:
ok found '93636728.0194890', expected '93636728.0195000', error '0.0000000'
Test #5:
score: 0
Accepted
time: 0ms
memory: 3900kb
input:
763961137 0.360268 233953864 630625466
output:
142908085.06960398
result:
ok found '142908085.0696040', expected '142908085.0700000', error '0.0000000'
Test #6:
score: 0
Accepted
time: 0ms
memory: 3884kb
input:
1000000000 0.999999 1 1000000000
output:
999999000.00000000
result:
ok found '999999000.0000000', expected '999999000.0000000', error '0.0000000'