Submission #364795

#	Time	Username	Problem	Language	Result	Execution time	Memory
364795		jainbot27	Lamps (JOI19_lamps)	C++17	100 / 100	293 ms	10348 KiB

lamp

#include <bits/stdc++.h>
using namespace std;

#define f first
#define s second
#define pb push_back
#define ar array
#define all(x) x.begin(), x.end()
#define siz(x) (int)x.size()

#define FOR(x, y, z) for(int x = (y); x < (z); x++)
#define ROF(x, z, y) for(int x = (y-1); x >= (z); x--)
#define F0R(x, z) FOR(x, 0, z)
#define R0F(x, z) ROF(x, 0, z)
#define trav(x, y) for(auto&x:y)

using ll = long long;
using vi = vector<int>;
using vl = vector<long long>;
using pii = pair<int, int>;
using vpii = vector<pair<int, int>>;

template<class T> inline bool ckmin(T&a, T b) {return b < a ? a = b, 1 : 0;}
template<class T> inline bool ckmax(T&a, T b) {return b > a ? a = b, 1 : 0;}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const char nl = '\n';
const int mxN = 1e6+10;
const int MOD = 1e9 + 7;
const long long infLL = 1e18;

int a[mxN], b[mxN], n; ar<int, 8> dp, new_dp;
char c;

int get(int idx, int msk){
    int res = a[idx];
    if(msk&1) res = 0;
    if(msk&2) res = 1;
    if(msk&4) res ^= 1;
    return res;
}

int32_t main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n;
    F0R(i, n) cin >> c, a[i] = c - '0';
    F0R(i, n) cin >> c, b[i] = c - '0';
    FOR(i, 1, 8) dp[i] = n;
    F0R(i, n){
        F0R(msk, 8){
            new_dp[msk] = n;
            if(get(i, msk)==b[i]){
                F0R(old_msk, 8){
                    ckmin(new_dp[msk], dp[old_msk]+__builtin_popcount(~old_msk&msk));
                }
            }
        }
        swap(dp, new_dp);
    }
    int ans = n;
    F0R(i, 8) ckmin(ans, dp[i]);
    cout << ans << nl;
    return 0;
}

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