NOI.AC
| 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 |
|---|---|---|---|---|---|---|---|---|---|
| #212173 | #3815. 种树 | chendongyu | 100 | 0ms | 1188kb | C++11 | 1.1kb | 2024-10-13 11:49:12 | 2024-10-13 12:56:21 |
answer
#include<bits/stdc++.h>
using namespace std;
long long n,m,k,ans;
long long f[26];
long long vis[20][20];
long long move_[4][2]={{1,0},{0,1},{-1,0},{0,-1}};
long long funny(long long x,long long y,long long sum)
{
sum--;
vis[x][y]++;
for(int i=0;i<4;i++)
{
int x1=x+move_[i][0];
int y1=y+move_[i][1];
if(x1&&y1&&x1<=n&&y1<=m)
{
if(!vis[x1][y1])
sum--;
vis[x1][y1]++;
}
}
return sum;
}
long long sadly(long long x,long long y)
{
vis[x][y]--;
for(int i=0;i<4;i++)
{
int x1=x+move_[i][0];
int y1=y+move_[i][1];
if(x1&&y1&&x1<=n&&y1<=m)
vis[x1][y1]--;
}
}
void dfs(int t,int num)
{
if(t==k-1)
{
ans+=num;
return;
}
for(int i=1;i<=n;i++)
{
for(int j=1;j<=m;j++)
{
if(vis[i][j]==false)
{
dfs(t+1,funny(i,j,num));
sadly(i,j);
}
}
}
}
int main()
{
f[0]=1;
for(int i=1;i<=20;i++)
f[i]=f[i-1]*i;
cin>>n>>m>>k;
if(n==1||m==1)
{
if(2*k>n*m)
ans=0;
else
ans=f[n*m-k]/f[n*m-2*k];
}
else
{
dfs(0,n*m);
}
printf("%lld",ans/f[k]);
return 0;
}
详细
小提示：点击横条可展开更详细的信息
Test #1:
score: 10
Accepted
time: 0ms
memory: 1184kb
input:
2 2 1
output:
4
result:
ok 1 number(s): "4"
Test #2:
score: 10
Accepted
time: 0ms
memory: 1184kb
input:
2 3 2
output:
8
result:
ok 1 number(s): "8"
Test #3:
score: 10
Accepted
time: 0ms
memory: 1188kb
input:
4 4 2
output:
96
result:
ok 1 number(s): "96"
Test #4:
score: 10
Accepted
time: 0ms
memory: 1184kb
input:
4 4 5
output:
304
result:
ok 1 number(s): "304"
Test #5:
score: 10
Accepted
time: 0ms
memory: 1188kb
input:
3 4 3
output:
84
result:
ok 1 number(s): "84"
Test #6:
score: 10
Accepted
time: 0ms
memory: 1188kb
input:
3 5 2
output:
83
result:
ok 1 number(s): "83"
Test #7:
score: 10
Accepted
time: 0ms
memory: 1188kb
input:
3 5 3
output:
215
result:
ok 1 number(s): "215"
Test #8:
score: 10
Accepted
time: 0ms
memory: 1188kb
input:
3 5 4
output:
276
result:
ok 1 number(s): "276"
Test #9:
score: 10
Accepted
time: 0ms
memory: 1184kb
input:
3 5 5
output:
174
result:
ok 1 number(s): "174"
Test #10:
score: 10
Accepted
time: 0ms
memory: 1184kb
input:
4 3 5
output:
18
result:
ok 1 number(s): "18"
Extra Test:
score: 0
Extra Test Passed
