foo.c: In function 'main':
foo.c:9:17: error: 'b' undeclared (first use in this function)
    9 |                 b=(a+32);
      |                 ^
foo.c:9:17: note: each undeclared identifier is reported only once for each function it appears in
foo.c:14:24: warning: comparison of constant '123' with boolean expression is always true [-Wbool-compare]
   14 |                 if(96<a<123)
      |                        ^
foo.c:14:22: warning: comparisons like 'X<=Y<=Z' do not have their mathematical meaning [-Wparentheses]
   14 |                 if(96<a<123)
      |                    ~~^~

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