foo.c: In function 'main':
foo.c:32:18: error: 'n1' undeclared (first use in this function); did you mean 'a1'?
   32 |  scanf("%d%d%d",&n1,&n2,&n3);
      |                  ^~
      |                  a1
foo.c:32:18: note: each undeclared identifier is reported only once for each function it appears in
foo.c:32:22: error: 'n2' undeclared (first use in this function); did you mean 'a2'?
   32 |  scanf("%d%d%d",&n1,&n2,&n3);
      |                      ^~
      |                      a2
foo.c:32:26: error: 'n3' undeclared (first use in this function); did you mean 'a3'?
   32 |  scanf("%d%d%d",&n1,&n2,&n3);
      |                          ^~
      |                          a3
foo.c:33:14: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   33 |  input(a1,n1),input(a2,n2),input(a3,n3);
      |              ^
foo.c:33:27: warning: left-hand operand of comma expression has no effect [-Wunused-value]
   33 |  input(a1,n1),input(a2,n2),input(a3,n3);
      |                           ^

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