foo.cc: In function 'int main()':
foo.cc:25:10: error: 'r' was not declared in this scope
    cout<<r;
          ^
foo.cc:8:12: warning: unused variable 'max' [-Wunused-variable]
  int n,i,t,max,count;
            ^~~
foo.cc:8:16: warning: unused variable 'count' [-Wunused-variable]
  int n,i,t,max,count;
                ^~~~~
foo.cc:9:6: warning: unused variable 'change' [-Wunused-variable]
  int change[N];
      ^~~~~~

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