View Compilation Error

0_0_24320495_32277.cpp:7:23: error: 'M' was not declared in this scope
 int e[N][N],q[N],flag[M],slack[N];ll ans;
                       ^
0_0_24320495_32277.cpp: In function 'void KM(int)':
0_0_24320495_32277.cpp:20:10: error: 'flag' was not declared in this scope
   memset(flag,0,sizeof(flag));
          ^