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.

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

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.