foo.c: In function 'main':
foo.c:8:39: warning: unused variable 'c' [-Wunused-variable]
  int a[100000]={1}, n=1,b[100000]={1},c[100000]={1}, m=1,k,o,p,q;   
                                       ^
foo.c: In function 'Add':
foo.c:45:12: warning: operation on 'i' may be undefined [-Wsequence-point]
  c[i++]=a[i++];
           ~^~
foo.c:20:10: warning: unused variable 'j' [-Wunused-variable]
  int i=0,j,jw=0,c[100000];
          ^
foo.c: In function 'Mul2':
foo.c:63:11: error: 'n' undeclared (first use in this function)
   Add(c,b,n,m);
           ^
foo.c:63:11: note: each undeclared identifier is reported only once for each function it appears in
foo.c:63:13: error: 'm' undeclared (first use in this function)
   Add(c,b,n,m);
             ^
foo.c:63:7: warning: passing argument 1 of 'Add' from incompatible pointer type [-Wincompatible-pointer-types]
   Add(c,b,n,m);
       ^
foo.c:18:6: note: expected 'int *' but argument is of type 'int (*)[100000]'
 void Add(int a[],int b[],int lena,int lenb)
      ^~~
foo.c: In function 'main':
foo.c:9:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&k,&o);
  ^~~~~~~~~~~~~~~~~~~
foo.c:10:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&q,&p);
  ^~~~~~~~~~~~~~~~~~~
foo.c: In function 'Mul2':
foo.c:65:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

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