foo.cc: In function 'int main()':
foo.cc:7:18: error: expected ';' before 's'
    7 |         l=2*(c+k)
      |                  ^
      |                  ;
    8 |         s=c*k
      |         ~         
foo.cc:5:19: warning: unused variable 's' [-Wunused-variable]
    5 |         int c,k,l,s;
      |                   ^

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