Submission #1230150

#	Time	Username	Problem	Language	Result	Execution time	Memory
1230150		hainam2k9	Lamps (JOI19_lamps)	C++20	100 / 100	48 ms	14116 KiB

lamp

#include <bits/stdc++.h>
#define tt cin.tie(0), cout.tie(0), ios_base::sync_with_stdio(0)
#define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
#define ll long long
#define ull unsigned long long
#define i128 __int128
#define db long double
#define sz(a) ((int)(a).size())
#define pb emplace_back
#define pf emplace_front
#define pob pop_back
#define pof pop_front
#define lb lower_bound
#define ub upper_bound
#define fi first
#define se second
#define ins emplace
#define mp make_pair
using namespace std;
const int MOD = 1e9+7, MAXN = 1e6+5;
const string NAME = "";
int n,dp[MAXN][3];
char a[MAXN],b[MAXN];
int main()
{
    tt;
    if(fopen((NAME + ".INP").c_str(), "r")) fo;
    cin >> n;
    for(int i = 1; i<=n; ++i)
        cin >> a[i];
    for(int i = 1; i<=n; ++i)
        cin >> b[i];
    memset(dp,0x3f,sizeof(dp));
    dp[0][0]=0;
    for(int i = 1; i<=n; ++i){
        for(int j = 0; j<3; ++j)
            for(int k = 0; k<3; ++k){
                if(j+k==3) continue;
                dp[i][j]=min(dp[i][j],dp[i-1][k]+(j>0&&k==0)+((i==1||(k==0 ? a[i-1] : k+47)==b[i-1])&&(j==0 ? a[i] : j+47)!=b[i]));
            }
    }
    cout << min({dp[n][0],dp[n][1],dp[n][2]});
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:3:19: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    3 | #define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
      |            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lamp.cpp:27:45: note: in expansion of macro 'fo'
   27 |     if(fopen((NAME + ".INP").c_str(), "r")) fo;
      |                                             ^~
lamp.cpp:3:63: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    3 | #define fo freopen((NAME+".INP").c_str(), "r", stdin), freopen((NAME+".OUT").c_str(), "w", stdout)
      |                                                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
lamp.cpp:27:45: note: in expansion of macro 'fo'
   27 |     if(fopen((NAME + ".INP").c_str(), "r")) fo;
      |                                             ^~

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