QOJ.ac

QOJ

ID题目提交者结果用时内存语言文件大小提交时间测评时间
#394509#244. Turn Off The Lightyanran100 ✓705ms16496kbC++143.3kb2024-04-20 15:29:212024-04-20 15:29:21

Judging History

你现在查看的是最新测评结果

  • [2024-04-20 15:29:21]
  • 评测
  • 测评结果:100
  • 用时:705ms
  • 内存:16496kb
  • [2024-04-20 15:29:21]
  • 提交

answer

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

typedef long long ll;
int read() {
	int x=0; char ch=getchar(); 
	while (!isdigit(ch)) ch=getchar(); 
	while (isdigit(ch)) x=x*10+ch-48, ch=getchar(); 
	return x; 
}

const int N=1e6+5, mod=1e9+7;
char s[N];
int a[N], n, L, R, cc;

ll C(int x) {
	int cnt=0, res=0;
	for (int i=1; i<=n; i++) cnt+=a[i];
	if (cnt&1) res++, a[x]^=1;
	for (int i=1, l=0; i<=n; i++) if (a[i]) {
		if (l) res+=2*(i-l), l=0;
		else l=i;
	}
	if (cnt&1) a[x]^=1;
	return res;
}
int rev(int l, int r) {
	for (int i=l; i<=r; i++) a[i]^=1;
	if ((r-l)&1) return cc;
	return cc^1;
}
int ask(int x) {
	int res=1;
	for (int i=1; i<=x; i++) res^=a[i];
	return res;
}
int Match() {
	int res=0;
	for (int i=1, l=0; i<=n; i++) if (a[i]) {
		if (l) res+=2*(i-l), l=0;// )
		else l=i;// (
	}
	return res;
}
ll res;
void New(const int x, const int y, int &las) {
	if (!a[x]&&!a[y]) {
//		cout<<"gua\n";
		if (las) res+=2;
		else res-=2;
	}  else if (!a[x]&&a[y]) {
		if (las) res+=2;
		else res-=2;
		las^=1;
	} else if (a[x]&&!a[y]) {
		if (las) res-=2;
		else res+=2;
		las^=1;
	} else {
		if (las) res-=2;
		else res+=2;
	}
}
ll t[N];
void solve() {
	n=read(), L=n, R=-1, cc=0;
	scanf("%s", s+1);
	for (int i=1; i<=n; i++) a[i]=s[i]&1;
	for (int i=1; i<=n; i++) if (a[i]) R=i, cc++;
	if (R==-1) return puts("0"), void();
	for (int i=n; i>=1; i--) if (a[i]) L=i;
	ll ans=0; cc&=1;
	int o=rev(2, R); res=0;
	if (o) a[R-1]^=1, res++;
	res+=Match();
	for (int i=1, las=1; i<L; i+=2) {
		ans=(ans+(res+R-i)*i)%mod;
		New(i+1, i+2, las);
	}
	rev(2, R);
	if (o) a[R-1]^=1;
	o=rev(3, R); res=0;
	if (o) a[R-1]^=1, res++;
	res+=Match();
	for (int i=2, las=ask(2); i<L; i+=2) {
		ans=(ans+(res+R-i)*i)%mod;
		New(i+1, i+2, las);
	}
	rev(3, R);
	if (o) a[R-1]^=1;
	o=rev(L, R), res=0;
	if (o) a[L+1]^=1, res++;
	res+=Match();
	for (int i=R+1, las=ask(R+1); i<=n; i+=2) {
		ans=(ans+(res+i-L)*i)%mod;
		New(i+1, i+2, las);
	}
	o=rev(L, R);
	if (o) a[L+1]^=1;
	o=rev(L, R+1), res=0;
	if (o) a[L+1]^=1, res++;
	res+=Match();
	for (int i=R+2, las=ask(R+2); i<=n; i+=2) {
		ans=(ans+(res+i-L)*i)%mod;
		New(i+1, i+2, las);
	}
	o=rev(L, R+1);
	if (o) a[L+1]^=1;
	if (L==R) return printf("%lld\n", ans+3*L), void();
	a[L]^=1, cc^=1;
	o=rev(L, R); res=0;
	if (o) a[R-1]^=1, res++;
	res+=Match();
	for (int i=L, las=ask(L-1); i<=R; i+=2) {
		t[i]=res+R-i+2*(i-L);
		New(i, i+1, las);
	}
	rev(L, R);
	if (o) a[R-1]^=1;
	o=rev(L+1, R), res=0;
	if (o) a[R-1]^=1, res++;
	res+=Match();
	for (int i=L+1, las=ask(L); i<=R; i+=2) {
		t[i]=res+R-i+2*(i-L);
		New(i, i+1, las);
	}
	rev(L+1, R);
	if (o) a[R-1]^=1;
	a[L]^=1;
	a[R]^=1;
	o=rev(L, L), res=0;
	if (o) a[L+1]^=1, res++;
	res+=Match();
	for (int i=L, las=ask(L); i<=R; i+=2) {
		t[i]=min(t[i], res+i-L+2*(R-i));
		New(i+1, i+2, las);
	}
	rev(L, L);
	if (o) a[L+1]^=1;
	o=rev(L, L+1), res=0;
	if (o) a[L+1]^=1, res++;
	res+=Match();
	for (int i=L+1, las=ask(L+1); i<=R; i+=2) {
		t[i]=min(t[i], res+i-L+2*(R-i));
		New(i+1, i+2, las);
	}
	rev(L, L+1);
	if (o) a[L+1]^=1;
	a[R]^=1, cc^=1;
	for (int i=L; i<=R; i++) 
		ans=(ans+t[i]*i)%mod;
	printf("%lld\n", ans%mod);
}

int main() {
	int T=read();
	while (T--) solve();
    return 0; 
}


详细

Test #1:

score: 100
Accepted
time: 705ms
memory: 16496kb

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