foo.cc: In function 'int main()':
foo.cc:7:10: warning: format '%d' expects a matching 'int*' argument [-Wformat=]
    7 |  scanf("%d,%d,&a,&b");
      |         ~^
      |          |
      |          int*
foo.cc:7:13: warning: format '%d' expects a matching 'int*' argument [-Wformat=]
    7 |  scanf("%d,%d,&a,&b");
      |            ~^
      |             |
      |             int*
foo.cc:7:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    7 |  scanf("%d,%d,&a,&b");
      |  ~~~~~^~~~~~~~~~~~~~~
foo.cc:8:3: warning: 'a' is used uninitialized in this function [-Wuninitialized]
    8 |  c=a;
      |  ~^~
foo.cc:9:3: warning: 'b' is used uninitialized in this function [-Wuninitialized]
    9 |  a=b;
      |  ~^~

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