View Compilation Error

0_0_31002037_22347.cpp: In function 'int main()':
0_0_31002037_22347.cpp:3:13: error: 'long' invalid for 'n'
  long float n,a,b;
             ^
0_0_31002037_22347.cpp:3:15: error: 'long' invalid for 'a'
  long float n,a,b;
               ^
0_0_31002037_22347.cpp:3:17: error: 'long' invalid for 'b'
  long float n,a,b;
                 ^
0_0_31002037_22347.cpp:4:19: error: 'long' invalid for 'c'
  long float c[3001];
                   ^
0_0_31002037_22347.cpp:6:13: error: 'long' invalid for 'sum'
  long float sum=n*a+b;
             ^
0_0_31002037_22347.cpp:7:13: error: 'long' invalid for 'i'
  long float i;
             ^
0_0_31002037_22347.cpp:9:19: error: invalid types 'float [3001][float]' for array subscript
   scanf("%lf",&c[i]);
                   ^
0_0_31002037_22347.cpp:10:16: error: invalid types 'float [3001][float]' for array subscript
   sum=sum-2*c[i]*(n-i);
                ^