foo.cc: In function 'int main()':
foo.cc:6:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d,%d",&n,&m);
      |  ~~~~~^~~~~~~~~~~~~~~
foo.cc:5:10: warning: 'i' may be used uninitialized in this function [-Wmaybe-uninitialized]
    5 |  int n,k,i,j,m;
      |          ^

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