Submission #100869

# Submission time Handle Problem Language Result Execution time Memory
100869 2019-03-15T00:52:18 Z cki86201 K-th path (IZhO11_kthpath) C++11
100 / 100
3 ms 512 KB
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <string>
#include <algorithm>
#include <iostream>
#include <functional>
#include <unordered_set>
#include <bitset>
#include <time.h>
#include <limits.h>

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define Fi first
#define Se second
#define pb(x) push_back(x)
#define szz(x) (int)x.size()
#define rep(i,n) for(int i=0;i<n;i++)
#define all(x) x.begin(),x.end()
typedef tuple<int, int, int> t3;

int N, M;
ll C[32][32], Co[72][72];
char X[32][32];
ll K;

int main() {
	rep(i, 72) {
		Co[i][0] = 1;
		for(int j=1;j<=i;j++) Co[i][j] = Co[i-1][j-1] + Co[i-1][j];
	}
	scanf("%d%d", &N, &M);
	for(int i=1;i<=N;i++) scanf("%s", X[i] + 1);
	scanf("%lld", &K);
	C[1][1] = 1;
	string ans; ans.pb(X[1][1]);
	for(int a=2;a<N+M;a++) {
		vector <pair<char, pii> > P;
		for(int x=1;x<=N;x++) {
			int y = a - x;
			if(1 <= y && y <= M) {
				if(x < N) C[x+1][y] += C[x][y];
				if(y < M) C[x][y+1] += C[x][y];
			}
		}
		ll cnt[30] = {};
		for(int x=1;x<=N;x++) {
			int y = a + 1 - x;
			if(1 <= y && y <= M) {
				cnt[X[x][y]-'a'] += C[x][y] * Co[N-x+M-y][N-x];
				P.pb(make_pair(X[x][y], pii(x, y)));
			}
		}
		char f = -1;
		for(int i=0;i<30;i++) {
			if(K > cnt[i]) K -= cnt[i];
			else { f = 'a' + i; break; }
		}
		ans.pb(f);
		rep(i, szz(P)) if(P[i].Fi != f) C[P[i].Se.Fi][P[i].Se.Se] = 0;
	}
	printf("%s\n", ans.c_str());
	return 0;
}

Compilation message

kthpath.cpp: In function 'int main()':
kthpath.cpp:42:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &N, &M);
  ~~~~~^~~~~~~~~~~~~~~~
kthpath.cpp:43:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i=1;i<=N;i++) scanf("%s", X[i] + 1);
                        ~~~~~^~~~~~~~~~~~~~~~
kthpath.cpp:44:7: 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 2 ms 512 KB Output is correct
2 Correct 2 ms 384 KB Output is correct
3 Correct 2 ms 384 KB Output is correct
4 Correct 2 ms 384 KB Output is correct
5 Correct 3 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 2 ms 384 KB Output is correct
8 Correct 3 ms 384 KB Output is correct
9 Correct 2 ms 384 KB Output is correct
10 Correct 2 ms 384 KB Output is correct
11 Correct 2 ms 384 KB Output is correct
12 Correct 2 ms 384 KB Output is correct
13 Correct 2 ms 384 KB Output is correct
14 Correct 2 ms 384 KB Output is correct
15 Correct 2 ms 384 KB Output is correct
16 Correct 2 ms 384 KB Output is correct
17 Correct 2 ms 384 KB Output is correct
18 Correct 2 ms 384 KB Output is correct
19 Correct 2 ms 384 KB Output is correct
20 Correct 2 ms 384 KB Output is correct