#include "bits/stdc++.h"
#define MAXN 100009
#define INF 1000000007
#define mp(x,y) make_pair(x,y)
#define all(v) v.begin(),v.end()
#define pb(x) push_back(x)
#define wr cout<<"----------------"<<endl;
#define ppb() pop_back()
#define tr(ii,c) for(__typeof((c).begin()) ii=(c).begin();ii!=(c).end();ii++)
#define ff first
#define ss second
#define my_little_dodge 46
#define debug(x) cerr<< #x <<" = "<< x<<endl;
using namespace std;
typedef long long ll;
typedef pair<int,int> PII;
template<class T>bool umin(T& a,T b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool umax(T& a,T b){if(a<b){a=b;return 1;}return 0;}
const int N=33;
const ll B=1e18+5;
char arr[N][N];
ll dp[N][N][2*N],C[2*N][2*N];
int n,m,sz;
string s,t;
void normalize(ll &a,ll b){
if(a>=B-b)
a=B;
else
a+=b;
}
ll way(int x,int y){
return C[x+y-2][x-1];
}
ll rec(int x,int y,int pos){
if(pos==sz-1)
return way(n-x+1,m-y+1);
ll &ret=dp[x][y][N];
if(~ret)
return ret;ret=0;
if(x+1<=n and arr[x+1][y]==t[pos+1])
normalize(ret,rec(x+1,y,pos+1));
if(y+1<=m and arr[x][y+1]==t[pos+1])
normalize(ret,rec(x,y+1,pos+1));
return ret;
}
ll solve(string x){
memset(dp,-1,sizeof dp);
sz=x.size();t=x;
return rec(1,1,0);
}
int main(){
//~ freopen("file.in", "r", stdin);
for(int i=0;i<N*2;i++)
C[i][0]=1;
for(int i=1;i<N*2;i++)
for(int j=1;j<=i;j++){
if(C[i-1][j]>=B-C[i-1][j-1])
C[i][j]=B;
else
C[i][j]=C[i-1][j]+C[i-1][j-1];
}
scanf("%d%d",&n,&m);
for(int i=1;i<=n;i++)
for(int j=1;j<=m;j++)
scanf(" %c",&arr[i][j]);
ll k;
scanf("%lld",&k);
s+=arr[1][1];
for(int i=0;i<n+m-2;i++)
for(int j=0;j<26;j++){
ll res=solve(s+char(j+97));
if(res>=k){
s+=char(j+97);
break;
}
k-=res;
}
puts(s.c_str());
return 0;
}
Compilation message
kthpath.cpp: In function 'int main()':
kthpath.cpp:63:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d",&n,&m);
^
kthpath.cpp:66:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf(" %c",&arr[i][j]);
^
kthpath.cpp:68:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%lld",&k);
^
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
2612 KB |
Output is correct |
2 |
Correct |
3 ms |
2612 KB |
Output is correct |
3 |
Correct |
6 ms |
2612 KB |
Output is correct |
4 |
Correct |
9 ms |
2612 KB |
Output is correct |
5 |
Correct |
3 ms |
2612 KB |
Output is correct |
6 |
Correct |
9 ms |
2612 KB |
Output is correct |
7 |
Correct |
13 ms |
2612 KB |
Output is correct |
8 |
Correct |
13 ms |
2612 KB |
Output is correct |
9 |
Correct |
13 ms |
2612 KB |
Output is correct |
10 |
Correct |
9 ms |
2612 KB |
Output is correct |
11 |
Correct |
16 ms |
2612 KB |
Output is correct |
12 |
Correct |
16 ms |
2612 KB |
Output is correct |
13 |
Correct |
23 ms |
2612 KB |
Output is correct |
14 |
Correct |
23 ms |
2612 KB |
Output is correct |
15 |
Correct |
26 ms |
2612 KB |
Output is correct |
16 |
Correct |
26 ms |
2612 KB |
Output is correct |
17 |
Correct |
26 ms |
2612 KB |
Output is correct |
18 |
Correct |
29 ms |
2612 KB |
Output is correct |
19 |
Correct |
29 ms |
2612 KB |
Output is correct |
20 |
Correct |
19 ms |
2612 KB |
Output is correct |