View Compilation Error

0_0_33877039_27094.cpp: In function 'int main()':
0_0_33877039_27094.cpp:8:16: error: 'n' was not declared in this scope
  for(int j=0;j<n;j++){
                ^
0_0_33877039_27094.cpp:16:9: error: 'a' was not declared in this scope
    cin>>a[i];
         ^
0_0_33877039_27094.cpp:23:13: error: 'a' was not declared in this scope
        if(((a[i+1]-a[i]-1)*d)>e){
             ^