foo.cc: In function 'int main()':
foo.cc:5:10: warning: unused variable 'i' [-Wunused-variable]
      int i,n,j,o,t=0;
          ^
foo.cc:5:14: warning: unused variable 'j' [-Wunused-variable]
      int i,n,j,o,t=0;
              ^
foo.cc:5:16: warning: unused variable 'o' [-Wunused-variable]
      int i,n,j,o,t=0;
                ^

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