#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;cin>>t;
    while(t--)
    {
        int n;cin>>n;
        int cnt=0;
        for(int i=0;i<n;i++)
        {
            int x;cin>>x;
            if(x%2!=0)cnt++;
        }
        if(cnt%2==0)cout<<"YES\n";
        else cout<<"NO\n";
    }
}

for i in range(int(input())):
    n=int(input())
    a=[*map(int,input().split())]
    cnt=0
    for i in range(n):
        if a[i]%2!=0:cnt+=1
    if cnt%2==0:print('YES')
    else:print('NO')

• Good task
• Average task
• Bad task
• Didn't solve

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;cin>>t;
    while(t--)
    {
        string s;cin>>s;
        s='0'+s;
        int p=s.size();
        for(int i=s.size()-1;i>=0;i--)
        {
            if(s[i]>='5')s[i-1]++,p=i;
        }
        for(int i=(s[0]=='0');i<s.size();i++)
        {
            cout<<(i>=p?'0':s[i]);
        }
        cout<<"\n";
    }
}

for i in range(int(input())):
    s=[0]+[*map(int,list(input()))]
    k=len(s)
    for i in range(len(s)-1,0,-1):
        if s[i]>4:s[i-1]+=1;k=i
    if s[0]!=0:print(s[0],end='')
    s=[*map(str,s)]
    print(''.join(s[1:k]+['0']*(len(s)-k)))

• Good task
• Average task
• Bad task
• Didn't solve

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int t;cin>>t;
    while(t--)
    {
        int n;cin>>n;
        int m=n*(n-1)/2,b[m];
        for(int i=0;i<m;i++)cin>>b[i];
        sort(b,b+m);
        for(int i=0;i<m;i+=--n)cout<<b[i]<<' ';
        cout<<"1000000000\n";
    }
}

for _ in range(int(input())):
    n=int(input())
    l=sorted(map(int,input().split()))
    j=0
    for i in range(n-1,0,-1):
        print(l[j],end=' ')
        j+=i
    print(l[-1])

• Good task
• Average task
• Bad task
• Didn't solve

#include<bits/stdc++.h>
using namespace std;
const int N=200005;
int a[N],b[N];
int main()
{
    int t;cin>>t;
    while(t--)
    {
        int n;cin>>n;
        for(int i=1;i<=n;i++)cin>>a[i];
        for(int i=1;i<=n;i++)cin>>b[i];
        int mx=INT_MIN;
        for(int i=1;i<=n;i++)mx=max(mx,a[i]-b[i]);
        int c=0;
        for(int i=1;i<=n;i++)c+=(a[i]-b[i]==mx);
        cout<<c<<"\n";
        for(int i=1;i<=n;i++)if(a[i]-b[i]==mx)cout<<i<<' ';
        cout<<"\n";
    }
}

for _ in range(int(input())):
    n=int(input())
    a=[*map(int,input().split())]
    b=[*map(int,input().split())]
    c=[a[i]-b[i] for i in range(n)]
    mx=max(c)
    ans=[]
    for i in range(n):
        if c[i]==mx:ans.append(i+1)
    print(len(ans))
    print(*ans)

• Good task
• Average task
• Bad task
• Didn't solve

#include<bits/stdc++.h>
using namespace std;
const int N=200005;
pair<int,int>x[N];
long long a[N];
int main()
{
    int t;cin>>t;
    while(t--)
    {
        int n;cin>>n;
        long long s1=0,s2=0;
        for(int i=1;i<=n;i++)
        {
            cin>>x[i].first;
            x[i].second=i;
            s2+=x[i].first;
        }
        sort(x+1,x+n+1);
        for(int i=1;i<=n;i++)
        {
            s2-=x[i].first;
            s1+=x[i].first;
            a[x[i].second]=n+1ll*x[i].first*(2*i-n)-s1+s2;
        }
        for(int i=1;i<=n;i++)cout<<a[i]<<" \n"[i==n];
    }
}

for i in range(int(input())):
    n=int(input())
    a=sorted([(b,i)for i,b in enumerate(map(int,input().split()))])
    ans=[0]*n
    s1=0
    s2=sum(a[i][0] for i in range(n))
    for i in range(n):
        ans[a[i][1]]=s2-a[i][0]*(n-i)+n-i+a[i][0]*i-s1+i
        s1+=a[i][0]
        s2-=a[i][0]
    print(*ans)

• Good task
• Average task
• Bad task
• Didn't solve

#include<bits/stdc++.h>
using namespace std;
map<long long,int>cnt;
long long my_sqrt(long long a)
{
    long long l=0,r=5000000001;
    while(r-l>1)
    {
        long long mid=(l+r)/2;
        if(1ll*mid*mid<=a)l=mid;
        else r=mid;
    }
    return l;
}
long long get(int b,long long c)
{
    long long D=1ll*b*b-4ll*c;
    if(D<0)return 0;
    long long x1=(b-my_sqrt(D))/2;
    long long x2=(b+my_sqrt(D))/2;
    if(x1+x2!=b||x1*x2!=c)return 0;
    if(x1==x2)return 1ll*cnt[x1]*(cnt[x1]-1)/2ll;
    else return 1ll*cnt[x1]*cnt[x2];
}
int main()
{
    int t;cin>>t;
    while(t--)
    {
        int n;cin>>n;
        cnt.clear();
        for(int i=1;i<=n;i++)
        {
            int x;cin>>x;
            cnt[x]++;
        }
        int q;cin>>q;
        for(int i=0;i<q;i++)
        {
            int b;long long c;
            cin>>b>>c;
            cout<<get(b,c)<<" \n"[i==q-1];
        }
    }
}

from collections import Counter
from math import sqrt
 
for _ in range(int(input())):
    n=int(input())
    a=[*map(int,input().split())]
    d=Counter(map(str,a))
    for i in range(int(input())):
        x,y=map(int,input().split())
        if x*x-4*y<0:print(0);continue
        D=int(sqrt(x*x-4*y))
        x1=(x+D)//2
        x2=(x-D)//2
        if x1+x2!=x or x1*x2!=y:print(0);continue
        if x1!=x2:print(d[str(x1)]*d[str(x2)])
        else:print(d[str(x1)]*(d[str(x1)]-1)//2)

• Good task
• Average task
• Bad task
• Didn't solve

#include<bits/stdc++.h>
using namespace std;
const int N=200000,mod=998244353;
int p[N+1],sz[N+1];
struct edge
{
    int u,v,w;
    void read(){cin>>u>>v>>w;}
    bool operator<(edge x){return w<x.w;}
}a[N+1];
int leader(int v)
{
    if(p[v]==v)return v;
    else return p[v]=leader(p[v]);
}
void unite(int u,int v)
{
    u=leader(u);
    v=leader(v);
    p[u]=v;
    sz[v]+=sz[u];
}
long long binpow(long long a,long long n)
{
    if(n==0)return 1;
    if(n%2==0)return binpow(a*a%mod,n/2);
    else return a*binpow(a,n-1)%mod;
}
int main()
{
    int t;cin>>t;
    while(t--)
    {
        int n,S;cin>>n>>S;
        for(int i=1;i<=n;i++)p[i]=i,sz[i]=1;
        for(int i=0;i<n-1;i++)a[i].read();
        sort(a,a+n-1);
        long long ans=1;
        for(int i=0;i<n-1;i++)
        {
            int sub_u=sz[leader(a[i].u)];
            int sub_v=sz[leader(a[i].v)];
            ans=ans*binpow(S-a[i].w+1,1ll*sub_u*sub_v-1)%mod;
            unite(a[i].u,a[i].v);
        }
        cout<<ans<<"\n";
    }
}

mod=998244353
def find_(v):
    stack=[v]
    while dsu[v]!=v:
        stack.append(dsu[v])
        v=stack[-1]
    while stack:
        dsu[stack[-1]]=dsu[v]
        v=stack.pop()
    return dsu[v]
 
for i in range(int(input())):
    n,S=map(int,input().split())
    l=[tuple(map(int,input().split()))for i in range(n-1)]
    l.sort(key=lambda x:x[2])
    ans=1
    dsu=[i for i in range(n)]
    coun=[1]*n
    for a,b,c in l:
        a-=1;b-=1
        if find_(a)!=find_(b):
            ans=ans*pow(S-c+1,coun[dsu[a]]*coun[dsu[b]]-1,mod)
            ans%=mod
            coun[dsu[a]]+=coun[dsu[b]]
            coun[dsu[b]]=0
            dsu[b]=dsu[a]
    print(ans)

• Good task
• Average task
• Bad task
• Didn't solve