/in/foo.cc: In function 'int main()':
/in/foo.cc:7:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    7 |         if(x%4==0&&x%100!=0||x%400==0)
      |            ~~~~~~^~~~~~~~~~
/in/foo.cc:5:15: warning: unused variable 'r4' [-Wunused-variable]
    5 |         int x,r4,r100,r400;
      |               ^~
/in/foo.cc:5:18: warning: unused variable 'r100' [-Wunused-variable]
    5 |         int x,r4,r100,r400;
      |                  ^~~~
/in/foo.cc:5:23: warning: unused variable 'r400' [-Wunused-variable]
    5 |         int x,r4,r100,r400;
      |                       ^~~~