foo.cc: In function 'int main()':
foo.cc:43:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%lf",&E);
     ~~~~~^~~~~~~~~~
foo.cc:45:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lf%lf%lf",&s[i],&k[i],&u[i]);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.cc: In function 'bool check(double)':
foo.cc:35:13: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
         v[i]=ans;
         ~~~~^~~~

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