# https://www.codechef.com/JUNE20B/problems/CHFICRM

https://www.codechef.com/JUNE20B/problems/CHFICRM
#include
#include
using namespace std;
int main()
{
int test;
cin>>test;
while(test–)
{

``````int n,i,sum,z,j;
vector<int>a;
cin>>n;
int flag=0;
for(i=0;i<n;i++)
{
cin>>z;
if(z==5 || z==10 || z==15)
a.push_back(z);
}

for(i=0;i<n;i++)
{
sum=0;
if(a[i]!=5)
{
a[i]=a[i]-5;
for(j=0;j<i && sum!=a[i];j++)
{
sum=sum+a[j];
if(a[j]!=0)
a[j]=a[j]-5;

}

if(sum!=(a[i]))
flag=1;
//a[i]=a[i]-5;
}
}
if(flag==1)
cout<<"NO"<<endl;
else
cout<<"YES"<<endl;
``````

}
}
what is the problem with my code ?

See this:

``````#include <bits/stdc++.h>
using namespace std;
int main(){
int t;
cin>>t;
while(t--){
int n;
cin>>n;
int x = 0, y = 0,q;//x for notes of 5 and y for notes of 10
//notes of 15 can't be used for any exchange, so just leave them
bool flag=true; //whether he could sell or not

for(int i=0;i<n;i++){
cin>>q;
if(q==15){
//for note of 15, choose 1 of y exchange over 2 of x
if(y>0){
y--;
}
//we don't have a y note now, we have to use 2 x notes
else if(x>1){
x-=2;
}
//if not possible, leave
else{
flag=false;
}
} else if(q==10){
//return 1 x note
if(x>0){
x--;
}
//if not possible, leave
else{
flag=false;
}
y++;//extra 10 note
} else {//now the note would be of 5
//so we get an extra x note
x++;
}
if(!flag)break;
}
if(flag){
cout<<"YES\n";
} else {
cout<<"NO\n";
}
}
return 0;
}
``````