foo.c: In function 'main':
foo.c:9:2: error: 'printf\U0000ff08' undeclared (first use in this function); did you mean 'printf'?
    9 |  printf（"请输入第二个整数："）;
      |  ^~~~~~~~
      |  printf
foo.c:9:2: note: each undeclared identifier is reported only once for each function it appears in
foo.c:9:10: error: expected ';' before string constant
    9 |  printf（"请输入第二个整数："）;
      |          ^~~~~~~~~~~~~~~~~~~~
      |          ;
foo.c:11:20: error: stray '\' in program
   11 |  printf ("%d+%d=%d"\n,x1,x2,x1+x2)
      |                    ^
foo.c:11:20: error: expected ')' before 'n'
   11 |  printf ("%d+%d=%d"\n,x1,x2,x1+x2)
      |         ~          ^~
      |                    )
foo.c:11:12: warning: format '%d' expects a matching 'int' argument [-Wformat=]
   11 |  printf ("%d+%d=%d"\n,x1,x2,x1+x2)
      |           ~^
      |            |
      |            int
foo.c:11:15: warning: format '%d' expects a matching 'int' argument [-Wformat=]
   11 |  printf ("%d+%d=%d"\n,x1,x2,x1+x2)
      |              ~^
      |               |
      |               int
foo.c:11:18: warning: format '%d' expects a matching 'int' argument [-Wformat=]
   11 |  printf ("%d+%d=%d"\n,x1,x2,x1+x2)
      |                 ~^
      |                  |
      |                  int
foo.c:11:35: error: expected ';' before 'printf'
   11 |  printf ("%d+%d=%d"\n,x1,x2,x1+x2)
      |                                   ^
      |                                   ;
   12 |  printf("%d*%d=%d"\n,x1,x2,x1*x2)
      |  ~~~~~~                            
foo.c:12:19: error: stray '\' in program
   12 |  printf("%d*%d=%d"\n,x1,x2,x1*x2)
      |                   ^
foo.c:13:9: warning: missing terminating " character
   13 |  printf("%d%%d=%d\n,x1,x2,x1%x2)
      |         ^
foo.c:13:9: error: missing terminating " character
   13 |  printf("%d%%d=%d\n,x1,x2,x1%x2)
      |         ^~~~~~~~~~~~~~~~~~~~~~~~
foo.c:15:11: error: invalid suffix "；" on integer constant
   15 |    return 0；
      |           ^~~
foo.c:16:1: error: expected declaration or statement at end of input
   16 | }
      | ^

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