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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 |
---|---|---|---|---|---|---|---|---|---|
#557295 | #9254. Random Variables | Larunatrecy | WA | 2ms | 9584kb | C++14 | 1.0kb | 2024-09-11 08:44:26 | 2024-09-11 08:44:31 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
template <typename T>inline void read(T &x)
{
x=0;char c=getchar();bool f=0;
for(;c<'0'||c>'9';c=getchar())f|=(c=='-');
for(;c>='0'&&c<='9';c=getchar())x=(x<<1)+(x<<3)+(c-'0');
x=(f?-x:x);
}
const int N = 1020;
int dp[N][N];
int n,m,mod,C[N][N];
void solve()
{
read(n);read(m);
int r=0,ans=0;
for(int k=1;k<=n;k++)
{
int lim=min(m,n/(k+1));
for(int i=0;i<=n;i++)
for(int j=lim;j>=0;j--)
if(i<=k)dp[i][j]=(i==0?1:1ll*dp[i-1][j]*(m-j)%mod);
else if(j<m)dp[i][j]=(1ll*dp[i-1][j]*(m-j)%mod-1ll*(m-j)*C[i-1][k]%mod*dp[i-(k+1)][j+1]%mod+mod)%mod;
int w=dp[n][0];
ans=(ans+1ll*k*(w-r+mod)%mod)%mod;r=w;
}
printf("%d\n",ans);
}
int main()
{
int T;
read(T);read(mod);
for(int i=0;i<=1000;i++)
{
C[i][0]=1;
for(int j=1;j<=i;j++)
C[i][j]=(C[i-1][j-1]+C[i-1][j])%mod;
}
while(T--)
{
solve();
}
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 2ms
memory: 9584kb
input:
3 123456789 3 2 5 5 7 7
output:
18 7145 2066323
result:
ok 3 lines
Test #2:
score: -100
Wrong Answer
time: 2ms
memory: 9236kb
input:
100 2 1 1 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 1 10 2 1 2 2 2 3 2 4 2 5 2 6 2 7 2 8 2 9 2 10 3 1 3 2 3 3 3 4 3 5 3 6 3 7 3 8 3 9 3 10 4 1 4 2 4 3 4 4 4 5 4 6 4 7 4 8 4 9 4 10 5 1 5 2 5 3 5 4 5 5 5 6 5 7 5 8 5 9 5 10 6 1 6 2 6 3 6 4 6 5 6 6 6 7 6 8 6 9 6 10 7 1 7 2 7 3 7 4 7 5 7 6 7 7 7 8 7 9 7 10 8 1 8 2...
output:
1 0 1 0 1 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 0 1 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 0 1 0 1 0 1 0 0 0 0 0 0 0 0 0
result:
wrong answer 31st lines differ - expected: '0', found: '1'