foo.c: In function 'ss':
foo.c:6:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(i==1)
  ^~
foo.c:8:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
   if(i==2)
   ^~
foo.c:5:8: warning: unused variable 'b' [-Wunused-variable]
  int a,b;
        ^
foo.c: In function 'main':
foo.c:20:8: warning: unused variable 'b' [-Wunused-variable]
  int a,b,c=1;
        ^
foo.c: In function 'ss':
foo.c:17:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.c: In function 'main':
foo.c:21:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&a);
    ^~~~~~~~~~~~~~

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