View Compilation Error

0_0_28394047_12751.cpp: In function 'void simulation()':
0_0_28394047_12751.cpp:33:22: error: 'INF' was not declared in this scope
             lb[i][j]=INF<<2;
                      ^
0_0_28394047_12751.cpp: In function 'int main()':
0_0_28394047_12751.cpp:68:19: error: 'INF' was not declared in this scope
         int L=0,R=INF;
                   ^