Submission #2620892


Source Code Expand

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define sqr(x) ((x)*(x))
#define mp make_pair
#define uint unsigned
#define PI pair<int,int>
inline char gc(){
    static char buf[100000],*p1=buf,*p2=buf;
    return p1==p2&&(p2=(p1=buf)+fread(buf,1,100000,stdin),p1==p2)?EOF:*p1++;
}
#define gc getchar
inline int read(){
	int x = 0; char ch = gc(); bool positive = 1;
	for (; !isdigit(ch); ch = gc())	if (ch == '-')	positive = 0;
	for (; isdigit(ch); ch = gc())	x = x * 10 + ch - '0';
	return positive ? x : -x;
}
inline void write(int a){
    if(a<0){
    	a=-a; putchar('-');
	}
    if(a>=10)write(a/10);
    putchar('0'+a%10);
}
inline void writeln(int a){
    if(a<0){
    	a=-a; putchar('-');
	}
	write(a); puts("");
}
inline int rnd(int x){
	return rand()%x;
}
inline ull rnd(){
	return ((ull)rand()<<30^rand())<<4|rand()%4;
}
const int N=4005,mod=1000000007;
int n,m,k,dp[N],ans;
inline void add(int &a,int b){
	a=a+b>=mod?a+b-mod:a+b;
}
signed main(){
	n=read(); m=read(); k=read(); swap(n,m);
	int jb=k-1;
	dp[0]=1; 
	for(int i=0;i<(n+m-1)/(k-1);i++){
		int meiju=min(n,i*(k-1)),mmm=min(n,(i+1)*(k-1));
		for(int j=1;j<=meiju;j++)add(dp[j],dp[j-1]);
		for(int j=meiju;j>=0;j--){
			if(j+k<=mmm)add(dp[j+k],mod-dp[j]);
			if(j+((n-j)%jb==0?jb:(n-j)%jb)<=n&&(i+1)*jb-(j+((n-j)%jb==0?jb:(n-j)%jb))<m)ans=(ans+dp[j])%mod;
			//cout<<dp[j]<<" "<<i<<" "<<j<<" "<<(i+1)*jb-(j+(n-j)%jb)<<endl;
		}
	}
	cout<<(ans+mod)%mod<<endl;
}

Submission Info

Submission Time
Task E - Eternal Average
User wzp
Language C++14 (GCC 5.4.1)
Score 1600
Code Size 1539 Byte
Status AC
Exec Time 56 ms
Memory 256 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 1600 / 1600
Status
AC × 3
AC × 27
Set Name Test Cases
Sample s1.txt, s2.txt, s3.txt
All 01.txt, 02.txt, 03.txt, 04.txt, 05.txt, 06.txt, 07.txt, 08.txt, 09.txt, 10.txt, 11.txt, 12.txt, 13.txt, 14.txt, 15.txt, 16.txt, 17.txt, 18.txt, 19.txt, 20.txt, 21.txt, 22.txt, 23.txt, 24.txt, s1.txt, s2.txt, s3.txt
Case Name Status Exec Time Memory
01.txt AC 1 ms 256 KB
02.txt AC 56 ms 256 KB
03.txt AC 1 ms 256 KB
04.txt AC 1 ms 256 KB
05.txt AC 29 ms 256 KB
06.txt AC 7 ms 256 KB
07.txt AC 1 ms 256 KB
08.txt AC 1 ms 256 KB
09.txt AC 3 ms 256 KB
10.txt AC 2 ms 256 KB
11.txt AC 2 ms 256 KB
12.txt AC 1 ms 256 KB
13.txt AC 2 ms 256 KB
14.txt AC 1 ms 256 KB
15.txt AC 2 ms 256 KB
16.txt AC 1 ms 256 KB
17.txt AC 1 ms 256 KB
18.txt AC 2 ms 256 KB
19.txt AC 3 ms 256 KB
20.txt AC 8 ms 256 KB
21.txt AC 1 ms 256 KB
22.txt AC 8 ms 256 KB
23.txt AC 2 ms 256 KB
24.txt AC 2 ms 256 KB
s1.txt AC 1 ms 256 KB
s2.txt AC 1 ms 256 KB
s3.txt AC 1 ms 256 KB