Submission #362059

#	Time	Username	Problem	Language	Result	Execution time	Memory
362059		Sparky_09	Round words (IZhO13_rowords)	C++17	76 / 100	990 ms	67180 KiB

rowords

#include "bits/stdc++.h"
using namespace std;
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define trav(a, x) for(auto& a : x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<pii> vpi;
 
void usaco(string s){
  freopen((s+".in").c_str(), "r", stdin);
  freopen((s+".out").c_str(), "w", stdout);
}
 
int n, m, start=0, ans = 0;
string s, t;
int dp[4100][2100];
pii before[4100][2100];
 
 
int main() {
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(cin.failbit);
#ifdef LOCAL_DEFINE
	freopen("input.txt", "r", stdin);
#endif
  cin >> s >> t;
  cerr << s << ' ' << t << '\n';
  n = s.size(); m = t.size();
  for(int i = 0; i < 4100; i++) for(int j = 0; j < 2100; j++) dp[i][j] = (int)1e9;
  dp[0][0] = 0;
  for(int i = 0; i <= 2*n; i++){
    for(int j = 0; j <= m; j++){
      if(i==0 and j==0) continue;
      //dp[i][j] = 1e9;
      
      if(j > 0 and dp[i][j] > dp[i][j-1] + 1){
        dp[i][j] = dp[i][j-1] + 1;
        before[i][j] = make_pair(i, j-1);
      }
      if(i > 0 and j > 0 and s[(i - 1)%n] ==  t[j-1] and dp[i][j] > dp[i-1][j-1] + 1){
        dp[i][j] = dp[i-1][j-1] + 1;
        before[i][j] = make_pair(i-1, j-1);
      }
      if(i > 0 and dp[i][j] > dp[i-1][j] + 1){
        dp[i][j] = dp[i-1][j] + 1;
        before[i][j] = make_pair(i-1, j);
      }
      //cerr << before[i][j].first << ' ' << before[i][j].second << ' ' << i << ' ' << j << '\n';
    }
  }
  
  auto back = [&](int n1, int m1){
  	int sub = 0;
  	int temp = 0;
  	cerr << n1 << ' ' << m1 << '\n';
    while(n1 != start or m1){
      n1 = before[n1][m1].first; m1 = before[n1][m1].second;
      sub++;
      if(temp<10)
      	cerr << "here" << ' ' << n1 << ' ' << m1 << '\n'; //here is the error
      temp++;
    }
    cerr<<"done";
    return sub;
  };
 
  auto newstart = [&](){
    int i = start, j = 1;
    while(j <= m and (before[i][j] != make_pair(i - 1, j - 1))){
      j++;
    }
    if(j > m){
      return;
    }
    before[i][j] = make_pair(i, j - 1);
    //move one forward start is ahead now, we process next set
    while(i < 2*n and j < m){
      if(before[i+1][j] == make_pair(i, j)){
        i++;
        before[i][j] = make_pair(i, j-1);
      }
      else if(before[i+1][j+1] == make_pair(i, j)){
        i++; j++;
        before[i][j] = make_pair(i, j-1);
      }
      else{
        j++;
      }
    }
    while(i < 2*n and before[i+1][j] == make_pair(i, j)){
      i++; before[i][j] = make_pair(i, j-1);
    }
  };
  start = 0;
  ans = max(ans, n + m - back(n, m));
  for(int i = 1; i < n; i++){
    start++; newstart();
    ans = max(ans, n+m-back(n+i,m));
  }
  reverse(t.begin(), t.end());
  memset(dp, 0x3f, sizeof dp);
  for(int i = 0; i <= 2*n; i++){
    for(int j = 0; j <= m; j++){
      if(i==0 and j==0) continue;
      if(i > 0 and dp[i][j] > dp[i-1][j] + 1){
        dp[i][j] = dp[i-1][j] + 1;
        before[i][j] = {i-1, j};
      }
      if(j > 0 and dp[i][j] > dp[i][j-1] + 1){
        dp[i][j] = dp[i][j-1] + 1;
        before[i][j] = {i, j-1};
      }
      if(i > 0 and j > 0 and s[(i - 1)%n] ==  t[j-1] and dp[i][j] > dp[i-1][j-1] + 1){
        dp[i][j] = dp[i-1][j] + 1;
        before[i][j] = {i-1, j-1};
      }
    }
  }
  start = 0;
  ans = max(ans, n + m - back(n, m));
  for(int i = 1; i < n; i++){
    start++; newstart();
    ans = max(ans, n+m-back(n+i,m));
  }
  cout << ans << '\n';
}

Compilation message (stderr)

rowords.cpp: In function 'void usaco(std::string)':
rowords.cpp:13:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   13 |   freopen((s+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
rowords.cpp:14:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   14 |   freopen((s+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 76 / 100