foo.cc: In function 'int main()':
foo.cc:5:13: warning: unused variable 'l' [-Wunused-variable]
    5 |     int a,b,l,s;
      |             ^
foo.cc:5:15: warning: unused variable 's' [-Wunused-variable]
    5 |     int a,b,l,s;
      |               ^
foo.cc:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d %d",&a,&b);
      |  ~~~~~^~~~~~~~~~~~~~~

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