View Compilation Error

0_0_39579487_1381.cpp:128:1: error: expected ',' or ';' before 'Z'
  128 | Z a[N];
      | ^
0_0_39579487_1381.cpp: In function 'void solve()':
0_0_39579487_1381.cpp:133:31: error: 'a' was not declared in this scope
  133 |     for(int i=1;i<=n;i++)cin>>a[i];
      |                               ^
0_0_39579487_1381.cpp:135:14: error: 'a' was not declared in this scope
  135 |         ans+=a[i]*a[n]*(a[i]+a[n]);
      |              ^