foo.cc: In function 'int main()':
foo.cc:11:15: warning: unused variable 'i' [-Wunused-variable]
  int n1,n2,n3,i;
               ^
foo.cc: In function 'int chaS(int*, int, int*, int, int*)':
foo.cc:56:8: warning: unused variable 'j' [-Wunused-variable]
  int i,j,n3=0;
        ^

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