foo.cc: In function 'int main()':
foo.cc:9:44: warning: unused variable 'l' [-Wunused-variable]
    9 |  int x1[100000]={0},x2[100000]={0},j=1,k=1,l=1;
      |                                            ^
foo.cc: In function 'int Mull(int*, int*, int, int)':
foo.cc:60:16: error: 'sum' was not declared in this scope
   60 |         memset(sum, 0, sizeof(sum));
      |                ^~~
foo.cc:60:9: error: 'memset' was not declared in this scope
   60 |         memset(sum, 0, sizeof(sum));
      |         ^~~~~~
foo.cc:3:1: note: 'memset' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    2 | #include <iostream>
  +++ |+#include <cstring>
    3 | using namespace std;
foo.cc:84:5: warning: no return statement in function returning non-void [-Wreturn-type]
   84 |     }
      |     ^

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