foo.cc: In function ‘int main()’:
foo.cc:7:23: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
    7 |         if(a<b || a=b && b<c || b=c)
      |                     ~~^~~~~~
foo.cc:7:30: error: lvalue required as left operand of assignment
    7 |         if(a<b || a=b && b<c || b=c)
      |                     ~~~~~~~~~^~~~