foo.c:3:1: error: unknown type name 'bool'; did you mean '_Bool'?
 bool isprime(int i)
 ^~~~
 _Bool
foo.c: In function 'isprime':
foo.c:6:10: error: 'false' undeclared (first use in this function); did you mean 'fabsl'?
   return false;
          ^~~~~
          fabsl
foo.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
foo.c:11:9: error: 'true' undeclared (first use in this function); did you mean 'trunc'?
  return true;
         ^~~~
         trunc
foo.c: In function 'main':
foo.c:31:26: error: 'true' undeclared (first use in this function); did you mean 'trunc'?
   if(t%i==0&&isprime(i)==true)
                          ^~~~
                          trunc
foo.c: In function 'isprime':
foo.c:12:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
foo.c: In function 'main':
foo.c:25:10: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  int n,m;scanf("%d%d",&n,&m);
          ^~~~~~~~~~~~~~~~~~~

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