foo.c: In function 'main':
foo.c:19:14: warning: unused variable 'i' [-Wunused-variable]
   19 |  int a,b,m,n,i;
      |              ^
foo.c:20:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   20 |  scanf("%d %d",&a,&b);
      |  ^~~~~~~~~~~~~~~~~~~~
foo.c: In function 's':
foo.c:8:12: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
    8 |     return m;
      |            ^
foo.c: In function 'z':
foo.c:14:3: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
   14 |  n=a*b/i;
      |  ~^~~~~~
foo.c: In function 'main':
foo.c:14:3: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
   14 |  n=a*b/i;
      |  ~^~~~~~
foo.c:4:6: note: 'm' was declared here
    4 |  int m,i;
      |      ^

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