View Compilation Error

0_0_21702989_20217.cpp: In function 'void init()':
0_0_21702989_20217.cpp:70:9: error: 'cost' was not declared in this scope
     clr(cost,inf);
         ^
0_0_21702989_20217.cpp:4:25: note: in definition of macro 'clr'
 #define clr(a,b) memset(a,b,sizeof(a));
                         ^