Submission #2106828
Source Code Expand
#include<cstdio>
#include<cstring>
#include<iostream>
#include<stdlib.h>
#include<ctime>
#include<string>
#include<cmath>
#include<algorithm>
#include<vector>
#include<set>
#include<map>
#include<queue>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define LL long long
#define FOR(i,a,b) for (int i=a;i<=b;i++)
#define FORD(i,a,b) for (int i=a;i>=b;i--)
using namespace std;
typedef pair<int,int> pa;
void getint(int &v){
char ch,fu=0;
for(ch='*'; (ch<'0'||ch>'9')&&ch!='-'; ch=getchar());
if(ch=='-') fu=1, ch=getchar();
for(v=0; ch>='0'&&ch<='9'; ch=getchar()) v=v*10+ch-'0';
if(fu) v=-v;
}
const int MO=1e9+7;
LL ans,fac[8010],inv[8010];
int n,v[4010][4010],tag[4010][4010],a[200010],b[200010];
LL pw(LL x,LL y){
LL t=1;
for (;y;y>>=1){
if (y&1) t=t*x%MO;
x=x*x%MO;
}
return t;
}
LL C(int x,int y){
return fac[x]*inv[y]%MO*inv[x-y]%MO;
}
int main(){
scanf("%d",&n);
FOR(i,1,n){
scanf("%d%d",&a[i],&b[i]);
v[2000-a[i]][2000-b[i]]++;
tag[2000+a[i]][2000+b[i]]++;
}
FOR(i,0,4000)
FOR(j,0,4000){
(v[i+1][j]+=v[i][j])%=MO;
(v[i][j+1]+=v[i][j])%=MO;
}
FOR(i,0,4000)
FOR(j,0,4000)
(ans+=1ll*v[i][j]*tag[i][j])%=MO;
fac[0]=1;
FOR(i,1,8000) fac[i]=fac[i-1]*i%MO;
inv[8000]=pw(fac[8000],MO-2);
FORD(i,7999,0) inv[i]=inv[i+1]*(i+1)%MO;
FOR(i,1,n)
(ans-=C(a[i]+a[i]+b[i]+b[i],a[i]+a[i]))%=MO;
ans=ans*pw(2,MO-2)%MO;
ans=(ans%MO+MO)%MO;
cout<<ans<<endl;
return 0;
}
Submission Info
Submission Time
2018-02-18 14:08:52+0900
Task
E - BBQ Hard
User
cwystc
Language
C++14 (GCC 5.4.1)
Score
1400
Code Size
1522 Byte
Status
AC
Exec Time
229 ms
Memory
96256 KB
Compile Error
./Main.cpp: In function ‘int main()’:
./Main.cpp:44:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
scanf("%d",&n);
^
./Main.cpp:46:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d",&a[i],&b[i]);
^
Judge Result
Set Name
Sample
All
Score / Max Score
0 / 0
1400 / 1400
Status
Set Name
Test Cases
Sample
sample-01.txt
All
sample-01.txt, 01-01.txt, 01-02.txt, 01-03.txt, 01-04.txt, 01-05.txt, 01-06.txt, 01-07.txt, 01-08.txt, 01-09.txt, 01-10.txt, 01-11.txt, 01-12.txt, 01-13.txt, 01-14.txt, sample-01.txt
Case Name
Status
Exec Time
Memory
01-01.txt
AC
175 ms
66048 KB
01-02.txt
AC
181 ms
94720 KB
01-03.txt
AC
204 ms
95488 KB
01-04.txt
AC
228 ms
96256 KB
01-05.txt
AC
229 ms
96256 KB
01-06.txt
AC
208 ms
65536 KB
01-07.txt
AC
175 ms
66048 KB
01-08.txt
AC
203 ms
67584 KB
01-09.txt
AC
208 ms
67584 KB
01-10.txt
AC
216 ms
81792 KB
01-11.txt
AC
221 ms
81920 KB
01-12.txt
AC
211 ms
71680 KB
01-13.txt
AC
229 ms
96256 KB
01-14.txt
AC
229 ms
96256 KB
sample-01.txt
AC
175 ms
66048 KB