Programming

#include<iostream>
int main(){
int i,j,key,n;
scanf("%d",&n);
int a[n];
for(i=0;i<n;i++) scanf("%d",&a[i]);
for(j=1;j<n;j++){
key=a[j];
i=j-1;
while(i>=0&&a[i]>key){
a[i+1]=a[i];
i=i-1;
}
a[i+1]=key;
} 
for(j=0;j<n;j++) printf("%d ",a[j]);
return 0;
}

                                 Error
In function 'int main()':
Line 10: error:             ISO C++ forbids variable-size array 'a'
compilation terminated             due to -Wfatal-errors.

int *a=new int[n];