foo.cc: In function 'int main()':
foo.cc:8:4: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
    if (a ==1);
    ^~
foo.cc:9:7: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
       while(a !=1)
       ^~~~~
foo.cc:7:6: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&a);
 ~~~~~^~~~~~~~~

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