foo.c: In function 'main':
foo.c:5:19: error: 'x' undeclared (first use in this function)
    5 |         int a[3]={x,y,z};
      |                   ^
foo.c:5:19: note: each undeclared identifier is reported only once for each function it appears in
foo.c:5:21: error: 'y' undeclared (first use in this function)
    5 |         int a[3]={x,y,z};
      |                     ^
foo.c:5:23: error: 'z' undeclared (first use in this function)
    5 |         int a[3]={x,y,z};
      |                       ^
foo.c:8:22: error: expected ';' before 'for'
    8 |         scanf("%d",z)
      |                      ^
      |                      ;
    9 |         for (i=0,i<2,i++)
      |         ~~~           
foo.c:5:13: warning: unused variable 'a' [-Wunused-variable]
    5 |         int a[3]={x,y,z};
      |             ^

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