View Compilation Error

0_0_13112278_13888.cpp: In function 'int main()':
0_0_13112278_13888.cpp:4:19: error: 'long long' invalid for 'a'
  long long double a,b,i,n;
                   ^
0_0_13112278_13888.cpp:4:21: error: 'long long' invalid for 'b'
  long long double a,b,i,n;
                     ^
0_0_13112278_13888.cpp:4:23: error: 'long long' invalid for 'i'
  long long double a,b,i,n;
                       ^
0_0_13112278_13888.cpp:4:25: error: 'long long' invalid for 'n'
  long long double a,b,i,n;
                         ^