foo.c: In function 'count_sum':
foo.c:5:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before '{' token
    5 | {
      | ^
foo.c:15:18: error: stray '\' in program
   15 |   printf("%d",sum\n）；
      |                  ^
foo.c:18: error: expected '{' at end of input

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