foo.c: In function 'main':
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~
foo.c:13:5: warning: 'sum' is used uninitialized in this function [-Wuninitialized]
   13 |  sum=sum+i;
      |  ~~~^~~~~~

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