foo.cc: In function 'int main()':
foo.cc:7:21: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
  if(a%400==0||a%4==0&&a%100!=0){
               ~~~~~~^~~~~~~~~~

正在同步测试数据，请稍后
自豪的采用HydroJudge(https://github.com/hydro-dev/Hydro)进行评测。