foo.cc:1:1: error: 'include' does not name a type; did you mean '__has_include'?
 include <stdio.h>
 ^~~~~~~
 __has_include
foo.cc: In function 'int main()':
foo.cc:8:2: error: 'scanf' was not declared in this scope
  scanf("%d%d%lf%lf%lf",&n,&m,&d,&first,&last);
  ^~~~~
foo.cc:10:3: error: 'printf' was not declared in this scope
   printf("%.3lf\n", m==1 ? first : last);
   ^~~~~~
foo.cc:10:3: note: suggested alternative: 'int'
   printf("%.3lf\n", m==1 ? first : last);
   ^~~~~~
   int
foo.cc:12:2: error: 'a' was not declared in this scope
  a[n][0] = 1;
  ^
foo.cc:20:2: error: 'printf' was not declared in this scope
  printf("%.3lf\n",a[m][0]*last + a[m][1]*t + a[m][2]*d);
  ^~~~~~
foo.cc:20:2: note: suggested alternative: 'int'
  printf("%.3lf\n",a[m][0]*last + a[m][1]*t + a[m][2]*d);
  ^~~~~~
  int

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