View Compilation Error

0_0_14800784_21177.cpp:38:7: error: 'a' does not name a type
 int n;a[N], b[N];
       ^
0_0_14800784_21177.cpp: In function 'int main()':
0_0_14800784_21177.cpp:48:25: error: 'a' was not declared in this scope
             scanf("%d", a + i);
                         ^
0_0_14800784_21177.cpp:52:25: error: 'b' was not declared in this scope
             scanf("%d", b + i);
                         ^
0_0_14800784_21177.cpp:55:26: error: 'b' was not declared in this scope
             v[i] = 1.0 * b[i] * b[i] * a[i] / 3.0;
                          ^
0_0_14800784_21177.cpp:55:40: error: 'a' was not declared in this scope
             v[i] = 1.0 * b[i] * b[i] * a[i] / 3.0;
                                        ^
0_0_14800784_21177.cpp:63:34: error: 'b' was not declared in this scope
                 double c = 1.0 * b[i] * (a[i] - mid) / a[i];
                                  ^
0_0_14800784_21177.cpp:63:42: error: 'a' was not declared in this scope
                 double c = 1.0 * b[i] * (a[i] - mid) / a[i];
                                          ^