/in/foo.c: In function 'main':
/in/foo.c:61:23: warning: statement with no effect [-Wunused-value]
  memset(a, 0, 100000);4
                       ^
/in/foo.c:62:2: error: expected ';' before 'int'
  int i, k;
  ^~~
/in/foo.c:63:27: error: 'k' undeclared (first use in this function)
  scanf("%d%d%d", &x, &n, &k);
                           ^
/in/foo.c:63:27: note: each undeclared identifier is reported only once for each function it appears in
/in/foo.c:66:3: error: 'i' undeclared (first use in this function)
   i = 1;
   ^