foo.cc:2:7: error: expected nested-name-specifier before 'namspace'
    2 | using namspace std;
      |       ^~~~~~~~
foo.cc: In function 'int main()':
foo.cc:6:15: error: 'cin' was not declared in this scope
    6 |         int b;cin>>a>>b;
      |               ^~~
foo.cc:8:9: error: 'cout' was not declared in this scope
    8 |         cout<<"YES"<<;
      |         ^~~~
foo.cc:8:22: error: expected primary-expression before ';' token
    8 |         cout<<"YES"<<;
      |                      ^
foo.cc:5:20: warning: unused variable 'cnt' [-Wunused-variable]
    5 |     unsigned int a,cnt=0;
      |                    ^~~

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