foo.cc: In function 'int main()':
foo.cc:4:6: warning: unused variable 'i' [-Wunused-variable]
    4 |  int i,j,t=0;
      |      ^
foo.cc:4:8: warning: unused variable 'j' [-Wunused-variable]
    4 |  int i,j,t=0;
      |        ^

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