please tell me the mistake in d program

#include<iostream.h>
using namespace std;
int main(){
int t;
cin>>t;
while(t–){
int n,m,f;
cin>>n>>m;
int a[m];
int y[n];
f=n;
int s=(n-m),k=1;
int b[s],c[s];
for(int i=1;i<=m;i++){
cin>>a[i];
}
for(int i=1;i<=n;i++)y[i]=i;

for(int i=1;i<=m;i++){
		for(int j=1;j<=n;j++){
			if(a[i]==y[j]){
			 for(int c=j;c<=f;c++){
			 	y[c]=y[c+1];
			 }f--;
			}}}

strong text

	for(int i=1;i<=s;i+=2){
if(y[i]>0)
	cout<<y[i]<<" ";
	else cout<<"\n";
	}cout<<"\n";
	for(int i=2;i<=s;i+=2){
	if(y[i]>0)cout<<y[i]<<" ";
	else cout<<"\n";
	}cout<<"\n";
	
}

}

hey if you have an array of size n then you can access the elements at indexes from 0 to n-1.we can’t access element at index n,but you are trying to access element at index n.

1.when you corrected your code and started it with 0 to index-1.while printing the values you didn’t checked the condition if(y[i]>0). May be that is causing the error.

2.y[c]=y[c+1] because of this code there is a garbage value at the end of array.which you remove by doing f–;.but when your code gets tested against multible types of input i doubt that garbage value remains which creates problem.

use 
fflush(stdin); 
//before this line 
cin>>n>>m; 
and see if your code works fine or not.

but if index starts at 1,then i can access the element at index n

no you can’t.

#include
using namespace std;
int main(){
int t;
cin>>t;
while(t–){
int n,m,f;
cin>>n>>m;
int a[m];
int y[n];
f=n;
int s=(n-m);
for(int i=0;i<m;i++){
cin>>a[i];
}
for(int i=0;i<n;i++)y[i]=(i+1);

for(int i=0;i<m;i++){
		for(int j=0;j<n;j++){
			if(a[i]==y[j]){//if element present in y[i] also,then delete it from y[i]
			 for(int c=j;c<f;c++){
			 	y[c]=y[c+1];
			 }f--;
			}
		}
	}
	for(int i=0;i<s;i+=2){
	cout<<y[i]<<" ";}cout<<"\n";
	for(int i=1;i<s;i+=2){
     cout<<y[i]<<" ";
	}cout<<"\n";
	
}

}

acc to you is it correct.

yes it is correct

but ,it is showing wrong ans.
plzz resolve dis

d que is from easy practice,cleaning up

here is my solution https://www.codechef.com/viewsolution/12060800
comment if you have any doubt

but acc to me,mine is not wrong,please help me in finding mistake in my pgm