Submission #915627

#	Time	Username	Problem	Language	Result	Execution time	Memory
915627		Whisper	K-th path (IZhO11_kthpath)	C++17	100 / 100	2 ms	468 KiB

kthpath

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;
using T = tuple<ll, ll, ll>;

#define int long long
#define Base 41
#define sz(a) (int)a.size()
#define FOR(i, a, b) for ( int i = a ; i <= b ; i++ )
#define FORD(i, a, b) for (int i = b; i >= a; i --)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPD(i, n) for (int i = n - 1; i >= 0; --i)
#define all(x) x.begin() , x.end()
#define pii pair<int , int>
#define fi first
#define se second
#define Lg(x) 31 - __builtin_clz(x)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)

constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int MAX = 51;
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

void setupIO(){
    #define name "Whisper"
    //Phu Trong from Nguyen Tat Thanh High School for gifted student
    srand(time(NULL));
    cin.tie(nullptr)->sync_with_stdio(false); cout.tie(nullptr);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    cout << fixed << setprecision(10);
}

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
int N, M, K;
char a[MAX][MAX];
char s[MAX];

int dp[MAX][MAX];

int f(int l, int r){
    int k = l + r - 1;
    if (s[k] != '#' && s[k] != a[l][r]) return 0;
    if (l == N && r == M) return 1;
    int &res = dp[l][r];
    if(~res) return res;
    res = 0;
    if (l + 1 <= N) res += f(l + 1, r);
    if (r + 1 <= M) res += f(l, r + 1);
    return res;
}

void Whisper(){
    cin >> N >> M;
    FOR(i, 1, N) FOR(j, 1, M) cin >> a[i][j];
    cin >> K;
    int l = N + M - 1;
    FOR(i, 1, l) s[i] = '#';
    for (int i = 1; i <= l; ++i){
        REP(c, 26){
            s[i] = (char)(c + 'a');
            memset(dp, -1, sizeof dp);
            if (f(1, 1) >= K) break;
            K -= f(1, 1);
        }
    }
    FOR(i, 1, l) cout << s[i];
}


signed main(){
    setupIO();
    int Test = 1;
//    cin >> Test;
    for ( int i = 1 ; i <= Test ; i++ ){
        Whisper();
        if (i < Test) cout << '\n';
    }
}

• Subtask 1: 100 / 100