Submission #954179

#	Time	Username	Problem	Language	Result	Execution time	Memory
954179		browntoad	Lamps (JOI19_lamps)	C++14	0 / 100	2 ms	4444 KiB

lamp

#include <bits/stdc++.h>
#pragma GCC optimize ("Ofast", "unroll-loops")
using namespace std;
#define ll long long
//#define int ll
#define FOR(i,a,b) for (int i = (a); i<(b); i++)
#define REP(i,n) FOR(i,0,n)
#define REP1(i,n) FOR(i,1,n+1)
#define RREP(i,n) for (int i=(n)-1; i>=0; i--)
#define RREP1(i,n) for (int i=(n); i>=1; i--)
#define f first
#define s second
#define pb push_back
#define ALL(x) x.begin(),x.end()
#define SZ(x) (int)(x.size())
#define SQ(x) (x)*(x)
#define pii pair<int, int>
#define pip pair<int, pii>
#define pdd pair<double ,double>
#define pcc pair<char, char>
#define endl '\n'
//#define TOAD
#ifdef TOAD
#define bug(x) cerr<<__LINE__<<": "<<#x<<" is "<<x<<endl
#define IOS()
#else
#define bug(...)
#define IOS() ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#endif
 
//const ll inf = 1ll<<60;
const int inf = (1ll<<30);
const ll mod = 998244353;
const ll maxn=1e6+5;
const ll maxm=5e4+5;
const double PI=acos(-1);
 
inline char gc()
{
    const static int SZ = 1 << 16;
    static char buf[SZ], *p1, *p2;
    if (p1 == p2 && (p2 = buf + fread(p1 = buf, 1, SZ, stdin), p1 == p2))
        return -1;
    return *p1++;
}
void rd() {}
template <typename T, typename... U>
void rd(T &x, U &...y)
{
    x = 0;
    bool f = 0;
    char c = gc();
    while (!isdigit(c))
        f ^= !(c ^ 45), c = gc();
    while (isdigit(c))
        x = (x << 1) + (x << 3) + (c ^ 48), c = gc();
    f && (x = -x), rd(y...);
}
 
template <typename T>
void prt(T x)
{
    if (x < 0)
        putchar('-'), x = -x;
    if (x > 9)
        prt(x / 10);
    putchar((x % 10) ^ 48);
}
 
ll pw(ll x, ll p, ll m=mod){
    ll ret=1;
    while (p>0){
        if (p&1){
            ret*=x;
            ret%=m;
        }
        x*=x;
        x%=m;
        p>>=1;
    }
    return ret;
}
 
ll inv(ll a, ll m=mod){
    return pw(a,m-2,m);
}
int dp[maxn][3];
bool chan[maxn][3];
int n;
signed main(){
    IOS();
  	rd(n);
    //string a, b; 
  	
  //cin>>a>>b;
  	char a[maxn], b[maxn];
  	scanf("%s%s",a+1,b+1);
    //a = '0'+a; b = '0'+b;
    dp[0][0] = 1;
    dp[0][1] = inf;
    dp[0][2] = 0;
    REP1(i, n){
        bool x = a[i]-'0', y = b[i]-'0';
        chan[i][0] = (y!=0);
        chan[i][1] = (y!=1);
        chan[i][2] = (x!=y);
        REP(j, 3){
            dp[i][j] = inf;
            REP(l, 3){
                dp[i][j] = min(dp[i][j], dp[i-1][l] + (j!=2 && l!=j) + (!chan[i-1][l] && chan[i][j]));
            }
        }
    }
  	int ans = min({dp[n][0], dp[n][1], dp[n][2]});
    prt(ans);
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:97:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   97 |    scanf("%s%s",a+1,b+1);
      |    ~~~~~^~~~~~~~~~~~~~~~

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