把问题转换为求区间内1为奇数的区间有多少个
那么直接记录从1开始为奇数和偶数的区间有多少就算出这个了
但是有不合法的就是只有1个1的区间
所以再减一下 重复的再加回来
#include <iostream>
#include <algorithm>
#include <sstream>
#include <string>
#include <queue>
#include <cstdio>
#include <map>
#include <set>
#include <utility>
#include <stack>
#include <cstring>
#include <cmath>
#include <vector>
#include <ctime>
#include <bitset>
using namespace std;
#define pb push_back
#define sd(n) scanf("%d",&n)
#define sdd(n,m) scanf("%d%d",&n,&m)
#define sddd(n,m,k) scanf("%d%d%d",&n,&m,&k)
#define sld(n) scanf("%lld",&n)
#define sldd(n,m) scanf("%lld%lld",&n,&m)
#define slddd(n,m,k) scanf("%lld%lld%lld",&n,&m,&k)
#define sf(n) scanf("%lf",&n)
#define sff(n,m) scanf("%lf%lf",&n,&m)
#define sfff(n,m,k) scanf("%lf%lf%lf",&n,&m,&k)
#define ss(str) scanf("%s",str)
#define ans() printf("%d",ans)
#define ansn() printf("%d\n",ans)
#define anss() printf("%d ",ans)
#define lans() printf("%lld",ans)
#define lanss() printf("%lld ",ans)
#define lansn() printf("%lld\n",ans)
#define fansn() printf("%.6f\n",ans)
#define r0(i,n) for(int i=0;i<(n);++i)
#define r1(i,e) for(int i=1;i<=e;++i)
#define rn(i,e) for(int i=e;i>=1;--i)
#define rsz(i,v) for(int i=0;i<(int)v.size();++i)
#define szz(x) ((int)x.size())
#define mst(abc,bca) memset(abc,bca,sizeof abc)
#define lowbit(a) (a&(-a))
#define all(a) a.begin(),a.end()
#define pii pair<int,int>
#define pli pair<ll,int>
#define pll pair<ll,ll>
#define mp make_pair
#define lrt rt<<1
#define rrt rt<<1|1
#define X first
#define Y second
#define PI (acos(-1.0))
#define sqr(a) ((a)*(a))
typedef long long ll;
typedef unsigned long long ull;
const ll mod = 1000000000+7;
const double eps=1e-9;
const int inf=0x3f3f3f3f;
const ll infl = 10000000000000000;
const int maxn= 200000+10;
const int maxm = 40000+10;
//Pretests passed
int in(int &ret)
{
char c;
int sgn ;
if(c=getchar(),c==EOF)return -1;
while(c!='-'&&(c<'0'||c>'9'))c=getchar();
sgn = (c=='-')?-1:1;
ret = (c=='-')?0:(c-'0');
while(c=getchar(),c>='0'&&c<='9')ret = ret*10+(c-'0');
ret *=sgn;
return 1;
}
char s[maxn];
int main()
{
#ifdef LOCAL
freopen("input.txt","r",stdin);
// freopen("output.txt","w",stdout);
#endif // LOCAL
int t;
sd(t);
while(t--)
{
int n;
sd(n);
ss(s+1);
ll x[2];
ll ans = 0;
int now = 0;
x[0] = 1;
x[1] = 0;
r1(i,n)
{
if(s[i]-'0')now^=1;
ans += x[now^1];
x[now]++;
}
int last = -1;
for(int i=1;i<=n;++i)
{
if(s[i]-'0')
{
if(last==-1)last = i;
else
{
ans -= i - last ;
last = i;
}
}
}
if(last!=-1&&last!=n)ans -= n + 1 - last;
else if(last==n)--ans;
last = -1;
for(int i=n;i>=1;--i)
{
if(s[i]-'0')
{
if(last==-1)last = i;
else
{
ans -= last - i ;
last = i;
}
}
}
if(last!=-1&&last!=1)ans -= last ;
else if(last==1)ans--;
r1(i,n)if(s[i]-'0')++ans;
lansn();
}
return 0;
}