Submission #203991

#	Time	Username	Problem	Language	Result	Execution time	Memory
203991		cheetose	Lamps (JOI19_lamps)	C++11	100 / 100	228 ms	22008 KiB

lamp

#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define X first
#define Y second
#define y0 y12
#define y1 y22
#define INF 987654321987654321
#define PI 3.141592653589793238462643383279502884
#define fup(i,a,b,c) for(int (i)=(a);(i)<=(b);(i)+=(c))
#define fdn(i,a,b,c) for(int (i)=(a);(i)>=(b);(i)-=(c))
#define MEM0(a) memset((a),0,sizeof(a));
#define MEM_1(a) memset((a),-1,sizeof(a));
#define ALL(a) a.begin(),a.end()
#define SYNC ios_base::sync_with_stdio(false);cin.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef double db;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> Pi;
typedef pair<ll, ll> Pll;
typedef pair<ld, ld> Pd;
typedef vector<int> Vi;
typedef vector<ll> Vll;
typedef vector<double> Vd;
typedef vector<Pi> VPi;
typedef vector<Pll> VPll;
typedef vector<Pd> VPd;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef tuple<ll, ll, ll> LLL;
typedef vector<iii> Viii;
typedef vector<LLL> VLLL;
typedef complex<double> base;
const int MOD = 998244353;
ll POW(ll a, ll b, ll MMM = MOD) { ll ret = 1; for (; b; b >>= 1, a = (a*a) % MMM)if (b & 1)ret = (ret*a) % MMM; return ret; }
ll gcd(ll a, ll b) { return b ? gcd(b, a%b) : a; }
ll lcm(ll a, ll b) { if (a == 0 || b == 0)return a + b; return a*(b / gcd(a, b)); }
int dx[] = { 0,1,0,-1,1,1,-1,-1 }, dy[] = { 1,0,-1,0,1,-1,1,-1 };

int a[1000005],b[1000005],d[3][1000005];
int main() {
	int n;
	scanf("%d",&n);
	fup(i,1,n,1)scanf("%1d",a+i);
	fup(i,1,n,1)scanf("%1d",b+i);
	d[0][1]=b[1]+1,d[1][1]=2-b[1],d[2][1]=a[1]!=b[1];
	fup(i,2,n,1)
	{
		d[0][i]=min(d[0][i-1]+(!b[i-1] && b[i]),d[2][i-1]+1+(a[i-1]==b[i-1] && b[i]));
		d[1][i]=min(d[1][i-1]+(b[i-1] && !b[i]),d[2][i-1]+1+(a[i-1]==b[i-1] && !b[i]));
		d[2][i]=min({
			d[2][i-1]+(a[i]!=b[i] && a[i-1]==b[i-1]),
			d[0][i-1]+(a[i]!=b[i] && !b[i-1]),
			d[1][i-1]+(a[i]!=b[i] && b[i-1])
		});
	}
	printf("%d\n",min({d[0][n],d[1][n],d[2][n]}));
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:46:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&n);
  ~~~~~^~~~~~~~~
lamp.cpp:47:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  fup(i,1,n,1)scanf("%1d",a+i);
              ~~~~~^~~~~~~~~~~
lamp.cpp:48:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  fup(i,1,n,1)scanf("%1d",b+i);
              ~~~~~^~~~~~~~~~~

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