Submission #173709

#	Time	Username	Problem	Language	Result	Execution time	Memory
173709		juggernaut	K-th path (IZhO11_kthpath)	C++14	0 / 100	38 ms	34808 KiB

kthpath

//Just try and the idea will come
#include<bits/stdc++.h>
#define int long long int
using namespace std;
set<pair<string,pair<int,int>>>st;
int n,m,i,j,x,y,dp[31][31],k;
string val,dis[31][31][31][31],res="";
pair<int,int>path[31][31][31][31],nxt[31][31][31][31];
char a[31][31];
main(){
    cin>>n>>m;
    dp[1][1]=1;
    for(i=1;i<=n;i++)
    for(j=1;j<=m;j++){
        cin>>a[i][j];
        dp[i][j]+=dp[i-1][j]+dp[i][j-1];
        for(int ii=1;ii<=n;ii++)
             for(int jj=1;jj<=m;jj++)dis[i][j][ii][jj]="zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz";
    }
    cin>>k;
    for(i=1;i<=n;i++)
    for(j=1;j<=m;j++){
                        dis[i][j][i][j]="";
                        dis[i][j][i][j]+=a[i][j];
                        st.insert({dis[i][j][i][j],{i,j}});
                        while(!st.empty()){
                            auto v=*st.begin();
                            x=v.second.first;
                            y=v.second.second;
                            val=v.first;
                            st.erase(st.begin());
                            if(x+1<=n&&val+a[x+1][y]<dis[i][j][x+1][y]){
                                st.erase({dis[i][j][x+1][y],{x+1,y}});
                                dis[i][j][x+1][y]=val+a[x+1][y];
                                path[i][j][x+1][y]={x,y};
                                st.insert({dis[i][j][x+1][y],{x+1,y}});
                            }
                            if(y+1<=m&&val+a[x][y+1]<dis[i][j][x][y+1]){
                                st.erase({dis[i][j][x][y+1],{x,y+1}});
                                dis[i][j][x][y+1]=val+a[x][y+1];
                                path[i][j][x][y+1]={x,y};
                                st.insert({dis[i][j][x][y+1],{x,y+1}});
                            }
                        }
                        x=n,y=m;
                        while(x&&y){
                            pair<int,int>tmp={x,y};
                            int xx=x;
                            x=path[i][j][x][y].first;
                            y=path[i][j][xx][y].second;
                            nxt[i][j][x][y]=tmp;
                        }}
    x=y=1;
    while(!(x==n&&y==m)){
        i=nxt[x][y][x][y].first;
        j=nxt[x][y][x][y].second;
        res+=a[x][y];
        if(k>dp[n-i+1][m-j+1]){
            k-=dp[n-i+1][m-j+1];
            if(i==x+1)y++;
            else x++;
        }else{
            x=i,y=j;
        }
    }
    res+=a[n][m];
    cout<<res;
}

Compilation message (stderr)

kthpath.cpp:10:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main(){
      ^

• Subtask 1: 0 / 100