QOJ.ac
QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #217423 | #6637. Perfect Strings | EastKing | WA | 24ms | 3948kb | C++17 | 646b | 2023-10-16 20:52:10 | 2023-10-16 20:52:10 |
Judging History
answer
#include<bits/stdc++.h>
using namespace std;
const int M=1e3+5,P=1e9+7;
int dp[2][M];
int main(){
int cas;
scanf("%d",&cas);
while(cas--){
int n,c;
scanf("%d %d",&n,&c);
int cur=0;
memset(dp[0],0,sizeof(dp[0]));
dp[0][0]=1;
for(int i=1;i<=2*n;i++){
int pre=cur;
cur^=1;
for(int j=0;j<=i;j++){
dp[cur][j]=0;
dp[cur][j]=(dp[cur][j]+dp[pre][j+1])%P;
if(j>0){
if(j>1)dp[cur][j]=(dp[cur][j]+1ll*dp[pre][j-1]*(c-1))%P;
else dp[cur][j]=(dp[cur][j]+1ll*dp[pre][j-1]*c)%P;
}
//printf("dp[%d][%d]=%d\n",i,j,dp[cur][j]);
}
}
printf("%d\n",dp[cur][0]);
}
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 0ms
memory: 3776kb
input:
2 3 1 2 2
output:
1 6
result:
ok 2 number(s): "1 6"
Test #2:
score: -100
Wrong Answer
time: 24ms
memory: 3948kb
input:
100000 1 1 4 1 5 5 3 5 1 2 5 3 1 1 3 3 5 2 2 1 4 1 5 5 2 3 4 1 3 3 2 5 3 2 4 3 4 4 3 5 3 1 5 2 2 2 4 2 5 4 1 2 3 1 4 5 2 5 5 3 1 5 5 2 3 2 5 2 4 1 1 3 3 2 4 5 2 1 4 1 2 2 1 1 3 5 4 5 2 3 3 5 2 5 2 4 5 4 2 3 1 1 2 1 4 4 1 5 5 4 1 3 5 4 4 5 1 3 1 1 3 3 2 4 2 4 2 1 5 5 1 3 2 3 4 1 4 3 2 4 2 4 4 2 1 1 1...
output:
1 1 71445 3678965 2 748396395 1 689688788 737208911 90470556 906419123 749486304 852967581 117268734 87 178289118 852625494 383947957 897711628 143457583 916481451 345420560 594870549 351888802 100884115 2 30951813 588453226 866817292 21740061 5 950183754 979407456 887245661 154848631 3 20 69675540 ...
result:
wrong answer 4th numbers differ - expected: '485', found: '3678965'