foo.c: In function 'main':
foo.c:6:1: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'scanf'
    6 | scanf("%d,%d",&a,&b);
      | ^~~~~
foo.c:7:23: error: 'a\U0000ff0bb' undeclared (first use in this function)
    7 |         printf("%d\n",a＋b);
      |                       ^~~~
foo.c:7:23: note: each undeclared identifier is reported only once for each function it appears in
foo.c:5:9: warning: unused variable 'a' [-Wunused-variable]
    5 |     int a,b
      |         ^

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