foo.cc: In function 'int main()':
foo.cc:14:13: warning: unused variable 's1' [-Wunused-variable]
         int s1 = sum[i-1];
             ^~
foo.cc:15:13: warning: unused variable 's2' [-Wunused-variable]
         int s2 ;
             ^~
foo.cc:5:9: warning: unused variable 'min' [-Wunused-variable]
     int min = 9999999,n,k;
         ^~~

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