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:9:1: error: 'scanf' was not declared in this scope
 scanf("%d%d%lf%lf%lf",&n,&m,&d,&first,&last);
 ^~~~~
foo.cc:11:1: error: 'printf' was not declared in this scope
 printf("%.3lf\n", m==1 ? first : last);
 ^~~~~~
foo.cc:11:1: note: suggested alternative: 'int'
 printf("%.3lf\n", m==1 ? first : last);
 ^~~~~~
 int
foo.cc:13:1: error: 'a' was not declared in this scope
 a[n][0] = 1;
 ^
foo.cc:21:1: 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:21:1: note: suggested alternative: 'int'
 printf("%.3lf\n",a[m][0]*last + a[m][1]*t + a[m][2]*d);
 ^~~~~~
 int

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