Submission #871679

#	Time	Username	Problem	Language	Result	Execution time	Memory
871679		Elvin_Fritl	K-th path (IZhO11_kthpath)	C++17	0 / 100	1 ms	348 KiB

kthpath

#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops")
///#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>

using namespace std;

/// toto -> 1

#define pb push_back
#define pii pair<int,int>
#define pll pair<ll,ll>
#define io                      \
    ios_base::sync_with_stdio(0); \
    cin.tie(0);                   \
    cout.tie(0);
#define all(a) a.begin(),a.end()
#define rep(k,i,n) for(int k=i;k<n;k++)
#define repp(k,i,n) for(int k=n-1;k>=i;k--)
#define rech(k) for(char k='a';k<='z';k++)
#define SZ(a) (int)a.size()
#define MX(a) *max_element(all(a))
#define MN(a) *min_element(all(a))
#define SM(a) accumulate(all(a),0LL)
#define vi vector<int>
#define vl vector<long long>
#define vvl vector<vector<long long>>
#define vvi vector<vector<int>>

/// toto -> 2

const int mod = 1e9 + 7 , modd = 998244353;


typedef long long ll;

void F1(bool res) {
    if(res) {
        cout<<"Yes\n" ;
    }
    else {
        cout<<"No\n" ;
    }
}

struct mint{
    ll val;

    mint(int64_t v = 0) {
        v %= mod;
        if (v < 0) v += mod;
        val = v;
    }

    mint& operator+=(const mint& other) {
        val += other.val;
        if (val >= mod) val -= mod;
        return *this;
    }

    mint& operator-=(const mint& other) {
        val += mod - other.val;
        if (val >= mod) val -= mod;
        return *this;
    }

    mint& operator*=(const mint& other) {
        val = (int64_t)val * other.val % mod;
        return *this;
    }

    mint& operator/=(const mint& other) {
        return *this *= other.inv();
    }

    friend mint operator+(mint a, const mint& b) { return a += b; }
    friend mint operator-(mint a, const mint& b) { return a -= b; }
    friend mint operator*(mint a, const mint& b) { return a *= b; }
    friend mint operator/(mint a, const mint& b) { return a /= b; }

    mint pow(int64_t exp) const {
        mint a = *this, res = 1;
        while (exp > 0) {
            if (exp & 1)
                res *= a;
            a *= a;
            exp >>= 1;
        }
        return res;
    }

    mint inv() const {
        assert(val != 0);
        return pow(mod - 2);
    }

    friend ostream& operator<<(ostream& os, const mint& m) {
        return os << m.val;
    }
};

ll bp(ll n,ll m){
    if(m == 0){
        return 1;
    }
    if(m == 1){
        return n%mod;
    }
    if(m%2==0){
        return bp(n*n%mod,m/2)%mod;
    }
    return n*bp(n,m-1)%mod;
}


/// toto -> 3

const int N = 2e5 + 544, M = 33, inf = 1e9 + 99;
const ll inff = 1e18;

int n,m;
ll k;
string res = "";
char c[M][M];
vvl dp(M , vl(M , -1)) , reset(M , vl(M , -1));

ll func(int x, int y){
    if (res[x + y] != c[x][y] && res[x + y] != '*'){
		return 0;
	}
    if(x == n - 1 && y == m - 1){
		return 1;
	}
    if(dp[x][y] != -1){
		return dp[x][y];
	}
    int tmp = 0;
 
    if(x + 1 < n){
        tmp += func(x+1,y);
    }
    if(y+1<m){
        tmp += func(x,y+1);
    }
 
	dp[x][y] = tmp;
 
    return tmp;
 
}
 
void solve(){
    cin>>n>>m;
    rep(i,0,n){
        rep(j,0,m){
            cin>>c[i][j];
        }
    }
    rep(i,0,n+m-1){
		res += '*';
	}
    cin>>k;
    res[0] = c[0][0];
    rep(i,1,n+m-1){
        rech(j){
            res[i] = j;
            dp = reset;
            ll x = func(0,0);
            if (x >= k){
				break;
			}
            k -= x;
        }
        if(k <= 0){
			break;
		}
    }
    cout << res << endl;;
}

int32_t main()
{

    io;
    
    ll t=1;
    ///  cin>>t;
    rep(_,1,t+1)
    {
        cerr << "Start of test case " << _ << "\n";
        ///cout<<"Case #"<<_<<": ";
        solve();
        cerr << endl;
        cerr << endl;
    }
    return 0;

}

• Subtask 1: 0 / 100