Owl Get a Life

Compile Error

platonic5.cpp: In function ‘int main()’:
platonic5.cpp:14:15: error: ‘i’ was not declared in this scope
14 | total += arr[i - 1] - arr[0];
| ^
platonic5.cpp:17:15: error: expected ‘}’ at end of input
17 | cout << total;
| ^
platonic5.cpp:5:14: note: to match this ‘{’
5 | signed main(){
| ^