View Compilation Error

0_0_23152226_25757.cpp:390:15: error: empty character constant
  else if (c ==''){
               ^
0_0_23152226_25757.cpp: In function 'int main()':
0_0_23152226_25757.cpp:346:16: error: 'sizeoflist' was not declared in this scope
  memset(list,0,sizeoflist);
                ^
0_0_23152226_25757.cpp:359:15: error: 'sizeofkey' was not declared in this scope
  memset(key,0,sizeofkey);
               ^
0_0_23152226_25757.cpp:362:18: error: 'sizeofanswer' was not declared in this scope
  memset(answer,0,sizeofanswer);
                  ^