foo.cc: In function 'int main()':
foo.cc:10:9: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   10 |     if(a=c)
      |        ~^~
foo.cc:5:13: warning: variable 'b' set but not used [-Wunused-but-set-variable]
    5 |     int n,a,b,c;
      |             ^

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