#include <iostream>

using namespace std;

int main()
{
    long long int n,q,i,j,k,m,d,p,x,f,c,h;
    for(m=1;;m++)
    {
        cin>>n;
        if(n==0)
        {
            break;
        }
        long long int a[n];
        for(i=0;i<n;i++)
        {
            cin>>a[i];
        }
        cin>>q;
        cout<<"Case "<<m<<":"<<endl;

        for(k=0;k<q;k++)
        {
            cin>>x;
            d=10000000000;
            c=0;
            for(i=0;i<n-1;i++)
            {
                for(j=i+1;j<n;j++)
                {
                    p=a[i]+a[j];
                    if(p==x)
                    {
                        h=p;
                        c=1;
                        break;
                    }
                    else if(p>x)
                    {
                        f=p-x;
                        if(f<d)
                        {
                            d=f;
                            h=p;
                        }
                    }
                    else if(p<x)
                    {
                        f=x-p;
                        if(f<d)
                        {
                            d=f;
                            h=p;
                        }
                    }
                }
                if(c==1)
                {
                    break;
                }
            }
            cout<<"Closest sum to "<<x<<" is "<<h<<"."<<endl;

        }
    }
    return 0;
}

#include <stdio.h>
#include <stdlib.h>

int main()

{
    int i,j,s,T;
    double sum,p,avrg,d,c;
    scanf("%d",&T);
    for(j=0;j<T;j++)
    {
        scanf("%d",&s);
        int A[s];
        for(i=0;i<s;i++)
        {
            scanf("%d",&A[i]);
        }
        sum=0;
        for(i=0;i<s;i++)
        {
            sum=sum+A[i];
        }
        d=s;
        avrg=(sum*1.0/d*1.0);
        c=0;
        for(i=0;i<s;i++)
        {
            if(A[i]>avrg)
            {
                c++;
            }
        }
        p=(c*1.0/s*1.0)*100;
        printf("%.3lf%%\n",p);
    }
    return 0;

}

#include <iostream>

using namespace std;

int main()
{
    long long int t,m,n,i,j,sum;
    cin>>t;
    for(i=0;i<t;i++)
    {
        cin>>n;
        m=n*3;
        long long int A[m];
        for(j=0;j<m;j++)
        {
            cin>>A[j];
        }
        sum=0;
        for(j=0;j<m-2;)
        {
            sum=sum+(A[j]*A[j+2]);
            j=j+3;
        }
        cout<<sum<<endl;

    }
    return 0;
}

Note:

I don’t remember why but I marked this problem as a “Tricky” problem when I solved this !!

#include <bits/stdc++.h>

using namespace std;

bool visit[3001];

int a[111111];

int main()
{
//    freopen("in.txt","r",stdin);
    int n,i,x,c,d;
    while(cin>>n)
    {
        memset(visit,0,sizeof(visit));
        for(i=0; i<n; i++)
        {
            cin>>a[i];
        }
        d=n-1;
        c=0;
        for(i=0; i<n-1; i++)
        {
            x=abs(a[i]-a[i+1]);
            if(visit[x])
            {
                c=1;
                break;
            }
            visit[x]=1;
        }


        if(c==0)
        {
            for(int i=1; i<n; i++)
                if(visit[i]==0)
                {
                    c=1;
                    break;
                }
        }

        if(c==0)
        {
            cout<<"Jolly"<<endl;
        }
        else
        {
            cout<<"Not jolly"<<endl;
        }

    }
    return 0;
}

#include <bits/stdc++.h>

#define ms(a,b)         memset(a,b,sizeof(a))
#define pb(a)           push_back(a)
#define db              double
#define ft              float
#define ll              long long
#define ull             unsigned long long
#define ff              first
#define ss              second
#define sz(x)           x.size()
#define qu              queue
#define pqu             priority_queue
#define vc              vector
#define vi              vector<int>
#define vll             vector<long long>
#define pii             pair<int,int>
#define pis             pair<int,string>
#define psi             pair<string,int>
#define all(x)          x.begin(),x.end()
#define CIN             ios_base::sync_with_stdio(0); cin.tie(0)
#define loop0(i,n)      for(int i=0;i<n;i++)
#define loop1(i,n)      for(int i=1;i<=n;i++)
#define stlloop(x)     for(__typeof(x.begin()) it=x.begin();it!=x.end();it++)
#define gcd(a, b)       __gcd(a, b)
#define lcm(a, b)       ((a)*((b)/gcd(a,b)))
#define case(z,x)       cout<<"Case "<<i<<": "<<x<<endl
#define case(z)         cout<<"Case "<<z<<": "
#define PI              3.14159265358979323846264338328
#define valid(tx,ty)    tx>=0 && tx<r && ty>=0 && ty<c
#define MAX             2000

/*----------------------Graph Moves----------------*/
//const int fx[]={+1,-1,+0,+0};
//const int fy[]={+0,+0,+1,-1};
//const int fx[]={+0,+0,+1,-1,-1,+1,-1,+1};   // Kings Move
//const int fy[]={-1,+1,+0,+0,+1,+1,-1,-1};  // Kings Move
//const int fx[]={-2, -2, -1, -1,  1,  1,  2,  2};  // Knights Move
//const int fy[]={-1,  1, -2,  2, -2,  2, -1,  1}; // Knights Move
/*------------------------------------------------*/

using namespace std;

int a[10];

int main()
{
    CIN;
//    freopen("in.txt","r",stdin);
//    freopen("out.txt","w",stdout);

    int t,x,y;
    cin>>t;
    loop1(z,t)
    {
        ms(a,0);
        int n;
        cin>>n;
        loop1(i,n)
        {
            x=i;
            while(x!=0)
            {
                y=x%10;
                a[y]++;
                x=x/10;
            }
        }
        cout<<a[0];
        loop1(i,9)
        {
            cout<<" "<<a[i];
        }
        cout<<endl;
    }

    return 0;
}