Submission #223534

#	Time	Username	Problem	Language	Result	Execution time	Memory
223534		kshitij_sodani	Lamps (JOI19_lamps)	C++17	100 / 100	75 ms	22008 KiB

lamp

#include <iostream>
#include <bits/stdc++.h>
using namespace std;
#define a first
#define b second
#define pb push_back
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n;
	cin>>n;
	int aa[n];
	int bb[n];
	char ss;
	for(int i=0;i<n;i++){
		cin>>ss;
		if(ss=='1'){
			aa[i]=1;
		}
		else{
			aa[i]=0;
		}
	}
	for(int i=0;i<n;i++){
		cin>>ss;
		if(ss=='1'){
			bb[i]=1;
		}
		else{
			bb[i]=0;
		}
	}
	int dp[n][3];
	if(aa[0]==bb[0]){
		dp[0][2]=0;
	}
	else{
		dp[0][2]=1;
	}
	if(bb[0]==1){
		dp[0][0]=2;
	}
	else{
		dp[0][0]=1;
	}
	if(bb[0]==0){
		dp[0][1]=2;
	}
	else{
		dp[0][1]=1;
	}

	for(int i=1;i<n;i++){
		for(int j=0;j<3;j++){
			dp[i][j]=n;
			//0
			int co=n;
			int x,y,z;
			x=dp[i-1][0];
			y=dp[i-1][1]+1;
			z=dp[i-1][2]+1;
			if(bb[i-1]==0 and bb[i]==1){
				x+=1;
			}
			if(bb[i-1]==1 and bb[i]==1){
				y+=1;
			}
			if(bb[i-1]==aa[i-1] and bb[i]==1){
				z+=1;
			}
			dp[i][0]=min(x,min(y,z));
			//1
			x=dp[i-1][0]+1;
			y=dp[i-1][1];
			z=dp[i-1][2]+1;
			if(bb[i-1]==0 and bb[i]==0){
				x+=1;
			}
			if(bb[i-1]==1 and bb[i]==0){
				y+=1;
			}
			if(bb[i-1]==aa[i-1] and bb[i]==0){
				z+=1;
			}
			dp[i][1]=min(x,min(y,z));
			//2
			x=dp[i-1][0];
			y=dp[i-1][1];
			z=dp[i-1][2];
			if(bb[i-1]==0 and bb[i]==1-aa[i]){
				x+=1;
			}
			if(bb[i-1]==1 and bb[i]==1-aa[i]){
				y+=1;
			}
			if(bb[i-1]==aa[i-1] and bb[i]==1-aa[i]){
				z+=1;
			}
			dp[i][2]=min(x,min(y,z));
		}
	}
	cout<<min(dp[n-1][0],min(dp[n-1][1],dp[n-1][2]))<<endl;
	return 0;
}

Compilation message (stderr)

lamp.cpp: In function 'int main()':
lamp.cpp:57:8: warning: unused variable 'co' [-Wunused-variable]
    int co=n;
        ^~

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