foo.c: In function 'main':
foo.c:12:13: warning: suggest parentheses around comparison in operand of '&' [-Wparentheses]
   12 |         if(i<1000&i>=100)
      |            ~^~~~~
foo.c:58:9: warning: 'm' may be used uninitialized [-Wmaybe-uninitialized]
   58 |         printf("%d",m);
      |         ^~~~~~~~~~~~~~
foo.c:4:21: note: 'm' was declared here
    4 |         int a,b,c,i,m;
      |                     ^
foo.c:18:9: warning: 'c' may be used uninitialized [-Wmaybe-uninitialized]
   18 |         switch(c)
      |         ^~~~~~
foo.c:4:17: note: 'c' was declared here
    4 |         int a,b,c,i,m;
      |                 ^

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