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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#396942#244. Turn Off The Lightyz_ly100 ✓253ms28264kbC++141.7kb2024-04-23 14:42:132024-04-23 14:42:13

Judging History

你现在查看的是最新测评结果

  • [2024-04-23 14:42:13]
  • 评测
  • 测评结果:100
  • 用时:253ms
  • 内存:28264kb
  • [2024-04-23 14:42:13]
  • 提交

answer

#include<bits/stdc++.h>
#define ll long long
using namespace std;
inline int read(){
	char ch=getchar();
	int f=1,x=0;
	while(ch<'0'||ch>'9'){
		if(ch=='-')
			f=-f;
		ch=getchar();
	}
	while(ch>='0'&&ch<='9'){
		x=x*10+ch-'0';
		ch=getchar();
	}
	return f*x;
}
inline void work(ll k){
	if(k<0){
		putchar('-');
		k=-k;
	}
	if(k>9)
		work(k/10);
	putchar(k%10+'0');
}
/*
策略很简单,走到最边上在走回去
dp维护不取反的一边,另一边动态维护
但是大模拟
*/
const ll mod=1e9+7;
int t,n;
ll ans[1000005],dp[1000005][2];
char s[1000005];
void solve(){
	int l=0,r=0;
	for(int i=1;i<=n;i++){
		if(s[i]=='1'){
			l=i;
			break;
		}
	}
	for(int i=n;i;i--){
		if(s[i]=='1'){
			r=i;
			break;
		}
	}
	dp[r-1][1]=2;
	dp[r-1][0]=1;
	for(int i=r-2;i>0;i--){
		dp[i][0]=dp[i+1][!(s[i+1]-'0')]+1;
		dp[i][1]=dp[i+1][s[i+1]-'0']+3;
	}
	for(int i=1,now=0,f=0;i<r;i++){
		if(i<l)
			ans[i]=min(dp[i][s[i]-'0'],ans[i]);
		else{
			ans[i]=min(ans[i],dp[i][f^(s[i]-'0')]+now);
			if((s[i]=='1')^f){
				f=1;
				now++;
			}
			else{
				now+=3;
				f=0;
			}
			now++;
		}
	}
}
int main(){
	t=read();
	while(t--){
		n=read();
		scanf("%s",s+1);
		int flag=0,num=0;
		for(int i=1;i<=n;i++){
			ans[i]=1e9;
			if(s[i]=='1')
				flag=1,num++;
		}
		if(!flag){
			puts("0");
			continue;
		}
		if(num==1){
			int id=0;
			for(int i=1;i<=n;i++){
				if(s[i]=='1')
					id=i;
			}
			ans[id]=3;
		}
		solve();
		reverse(s+1,s+n+1);
		reverse(ans+1,ans+n+1);
		solve();
		reverse(ans+1,ans+n+1);
		ll sum=0;
		for(int i=1;i<=n;i++){
			sum+=ans[i]*i%mod;
			sum%=mod;
		}
		work(sum);
		putchar('\n');
	}
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 253ms
memory: 28264kb

input:

146645
2
00
2
10
2
01
2
11
3
000
3
100
3
010
3
110
3
001
3
101
3
011
3
111
4
0000
4
1000
4
0100
4
1100
4
0010
4
1010
4
0110
4
1110
4
0001
4
1001
4
0101
4
1101
4
0011
4
1011
4
0111
4
1111
5
00000
5
10000
5
01000
5
11000
5
00100
5
10100
5
01100
5
11100
5
00010
5
10010
5
01010
5
11010
5
00110
5
10110
5...

output:

0
5
7
6
0
14
10
12
14
24
12
26
0
34
22
36
18
40
20
38
26
60
40
58
24
62
42
60
0
69
47
66
33
80
50
83
31
90
60
93
34
87
57
80
45
120
90
123
64
117
87
110
42
123
93
120
67
118
88
129
0
123
89
126
63
128
86
125
49
150
108
147
70
153
111
152
51
168
126
165
88
171
129
170
54
165
123
168
85
154
112
159
73...

result:

ok 146645 lines