View Compilation Error

0_0_36027828_19980.cpp: In function 'void Solve()':
0_0_36027828_19980.cpp:37:56: error: 'lfabs' was not declared in this scope
    if((zi+i>0)&&lfabs(1e6*(zi+i)*ansmu-1e6*pre*mu*ansmu)<lfabs(1e6*anszi*mu-1e6*pre*mu*ansmu)){
                                                        ^