View Compilation Error

0_0_26720670_29095.cpp: In function 'int S2(int, int, int)':
0_0_26720670_29095.cpp:81:22: error: 'v' was not declared in this scope
   return visS2[a][b][v] = abs((P[b] - P[a]) * (P[c] - P[a]));
                      ^