View Compilation Error

0_0_39285255_11213.cpp: In function 'double check(double)':
0_0_39285255_11213.cpp:3:5: error: 'r' was not declared in this scope
    3 |     r[1] = radius;
      |     ^
0_0_39285255_11213.cpp:4:25: error: 'n' was not declared in this scope
    4 |     for (int i = 1; i < n; i++) {
      |                         ^
0_0_39285255_11213.cpp:5:17: error: 'a' was not declared in this scope
    5 |         Sum += (a[i] - r[i]) * (a[i] - r[i]);
      |                 ^
0_0_39285255_11213.cpp:8:18: error: 'pi' was not declared in this scope
    8 |     return Sum * pi;
      |                  ^~