foo.cc: In function 'int main()':
foo.cc:2:52: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    2 | using namespace std;int main(){int a,b;char c;scanf("%d,%d,%c",&a,&b,&c);if(c=='+') cout<<a+b;else if(c=='-') cout<<a-b; else if(c=='*') cout<<a*b;else cout<<a/b;return 0;}
      |                                               ~~~~~^~~~~~~~~~~~~~~~~~~~~

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