Submission #104591

#	Time	Username	Problem	Language	Result	Execution time	Memory
104591		antimirage	Lamps (JOI19_lamps)	C++14	0 / 100	141 ms	67852 KiB

lamp

# include <bits/stdc++.h>

using namespace std;

const int N = 2005;

int n, dp[N][N][2], pref[N][2], fl[N];

string a, b;

int calc (int l, int r, int type){

      if (l > r) return 0;

      if (dp[l][r][type] < 1e9) return dp[l][r][type];

      int &ans = dp[l][r][type];

      if (type == 0){

            if ( a[l] == b[l] ){
                  ans = calc(l + 1, r, type);
                  return ans;
            }
            if ( a[r] == b[r] ){
                  ans = calc(l, r - 1, type);
                  return ans;
            }

            ans = min(ans, pref[r][0] );
      }
}

main(){

      memset( dp, 0x3f3f3f3f, sizeof(dp) );

      cin >> n >> a >> b;

      a = ' ' + a;
      b = ' ' + b;

      for (int i = 1; i <= n; i++){

            if (i > 1 && a[i] != a[i - 1])
                  fl[i]++;

            fl[i] += fl[i - 1];

            if (b[i] != b[i - 1])
                  pref[i][ b[i] - 48 ] = 1;

            pref[i][0] += pref[i - 1][0];
            pref[i][1] += pref[i - 1][1];
      }
      assert(fl[n] == 0);

      cout << pref[n][1] << endl;

//      calc(1, n, 0);
//      calc(1, n, 1);
//
//      cout << min( dp[1][n][0], dp[1][n][1] ) << endl;
}

Compilation message (stderr)

lamp.cpp:34:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main(){
      ^
lamp.cpp: In function 'int calc(int, int, int)':
lamp.cpp:32:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

• Subtask 1: 0 / 6
• Subtask 2: 0 / 41
• Subtask 3: 0 / 4
• Subtask 4: 0 / 49