View Compilation Error

0_0_21824827_28160.cpp: In function 'void mark(int, int, int)':
0_0_21824827_28160.cpp:6:8: error: 'i' was not declared in this scope
   flag[i][m
        ^
0_0_21824827_28160.cpp:7:2: error: expected ']' before 'for'
  for (int i=1;i<=k;++i)
  ^
0_0_21824827_28160.cpp: In function 'int main()':
0_0_21824827_28160.cpp:48:29: error: 'memset' was not declared in this scope
   memset(flag,0,sizeof(flag));
                             ^