View Compilation Error

0_0_39064862_10088.cpp: In function 'int count_locks(int)':
0_0_39064862_10088.cpp:20:21: error: 'abs' was not declared in this scope
   20 |                 if (abs(j - d) == 3 && d != j) {
      |                     ^~~
0_0_39064862_10088.cpp:31:27: error: expected ';' at end of input
   31 |     for (int d = 1; d <= 4
      |                           ^
      |                           ;
0_0_39064862_10088.cpp:31:27: error: expected primary-expression at end of input
0_0_39064862_10088.cpp:31:27: error: expected ')' at end of input
   31 |     for (int d = 1; d <= 4
      |         ~                 ^
      |                           )
0_0_39064862_10088.cpp:31:27: error: expected statement at end of input
0_0_39064862_10088.cpp:31:27: error: expected '}' at end of input
0_0_39064862_10088.cpp:5:24: note: to match this '{'
    5 | int count_locks(int N) {
      |                        ^