A. Nephren gives a riddle

Posted 2020-10-30 planche

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What are you doing at the end of the world? Are you busy? Will you save us?

$技术分享图片$

Nephren is playing a game with little leprechauns.

She gives them an infinite array of strings, f0... ∞.

f0 is "What are you doing at the end of the world? Are you busy? Will you save us?".

She wants to let more people know about it, so she defines fi = "What are you doing while sending "fi - 1"? Are you busy? Will you send "fi - 1"?" for all i ≥ 1.

For example, f1 is

"What are you doing while sending "What are you doing at the end of the world? Are you busy? Will you save us?"? Are you busy? Will you send "What are you doing at the end of the world? Are you busy? Will you save us?"?". Note that the quotes in the very beginning and in the very end are for clarity and are not a part of f1.

It can be seen that the characters in fi are letters, question marks, (possibly) quotation marks and spaces.

Nephren will ask the little leprechauns q times. Each time she will let them find the k-th character of fn. The characters are indexed starting from 1. If fn consists of less than k characters, output ‘.‘ (without quotes).

Can you answer her queries?

Input

The first line contains one integer q (1 ≤ q ≤ 10) — the number of Nephren‘s questions.

Each of the next q lines describes Nephren‘s question and contains two integers n and k (0 ≤ n ≤ 105, 1 ≤ k ≤ 1018).

Output

One line containing q characters. The i-th character in it should be the answer for the i-th query.

Examples

input

Copy

3
1 1
1 2
1 111111111111

output

Copy

Wh.

input

Copy

output

Copy

abdef

input

Copy

output

Copy

Areyoubusy

Note

For the first two examples, refer to f0 and f1 given in the legend.

长度预处理+递归

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define inf 2147483647
const ll INF = 0x3f3f3f3f3f3f3f3fll;
#define ri register int
template <class T> inline T min(T a, T b, T c)
{
    return min(min(a, b), c);
}
template <class T> inline T max(T a, T b, T c)
{
    return max(max(a, b), c);
}
template <class T> inline T min(T a, T b, T c, T d)
{
    return min(min(a, b), min(c, d));
}
template <class T> inline T max(T a, T b, T c, T d)
{
    return max(max(a, b), max(c, d));
}
#define scanf1(x) scanf("%d", &x)
#define scanf2(x, y) scanf("%d%d", &x, &y)
#define scanf3(x, y, z) scanf("%d%d%d", &x, &y, &z)
#define scanf4(x, y, z, X) scanf("%d%d%d%d", &x, &y, &z, &X)
#define pi acos(-1)
#define me(x, y) memset(x, y, sizeof(x));
#define For(i, a, b) for (int i = a; i <= b; i++)
#define FFor(i, a, b) for (int i = a; i >= b; i--)
#define bug printf("***********\n");
#define mp make_pair
#define pb push_back
const int N = 100005;
// name*******************************
ll len1,len2,len3;
ll f[N];
string s0="What are you doing at the end of the world? Are you busy? Will you save us?";
string s1="What are you doing while sending \"";
string s2="\"? Are you busy? Will you send \"";
string s3="\"?";
int q,n;
// function******************************
void init()
{
    f[0]=s0.size();
    len1=s1.size();
    len2=s2.size();
    len3=s3.size();
    For(i,1,N)
    {
        if(f[i-1]>=INF)
        {
            f[i]=INF;
            continue;
        }
        f[i]=len1+f[i-1]+len2+f[i-1]+len3;
    }
}

void solve(ll n,ll k)
{
    if(n==0)
    {
        printf("%c",s0[k-1]);
        return;
    }
    if(k<=len1)
    {
        printf("%c",s1[k-1]);
    }
    else if(k<=len1+f[n-1])
    {
        solve(n-1,k-len1);
    }
    else if(k<=len1+f[n-1]+len2)
    {
        printf("%c",s2[k-len1-f[n-1]-1]);
    }
    else if(k<=len1+f[n-1]+len2+f[n-1])
    {
        solve(n-1,k-len1-f[n-1]-len2);
    }
    else
    {
        printf("%c",s3[k-len1-f[n-1]-len2-f[n-1]-1]);
    }
}

//***************************************
int main()
{
//    ios::sync_with_stdio(0);
//    cin.tie(0);
    // freopen("test.txt", "r", stdin);
    //  freopen("outout.txt","w",stdout);
    scanf("%d",&q);
    init();
    while(q--)
    {
        ll a,b;
        scanf("%lld%lld",&a,&b);
        if(f[a]<b)
        {
            printf(".");
            continue;
        }
        solve(a,b);
    }

    return 0;
}

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