foo.c: In function 'main':
foo.c:25:9: error: expected '(' before 'b'
         b = a/100;
         ^
foo.c:32:9: error: 'else' without a previous 'if'
         else
         ^~~~
foo.c:35:8: error: 'else' without a previous 'if'
        else
        ^~~~
foo.c:38:7: error: 'else' without a previous 'if'
       else
       ^~~~
foo.c:41:6: error: 'else' without a previous 'if'
      else
      ^~~~
foo.c:44:5: error: 'else' without a previous 'if'
     else
     ^~~~
foo.c:47:4: error: 'else' without a previous 'if'
    else
    ^~~~
foo.c:50:3: error: 'else' without a previous 'if'
   else
   ^~~~
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &a);
  ^~~~~~~~~~~~~~~

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