foo.c: In function ‘main’:
foo.c:6:27: warning: unknown escape sequence: '\040'
    6 |         scanf("%d\ %d\ %d",&year,&month,&day);
      |                           ^
foo.c:6:27: warning: unknown escape sequence: '\040'
foo.c:32:34: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses]
   32 |                 else if(year%4==0&&year%100!=0||year%400==0){
      |                         ~~~~~~~~~^~~~~~~~~~~~~
foo.c:35:12: warning: ‘change’ may be used uninitialized [-Wmaybe-uninitialized]
   35 |         sum+=change;
      |         ~~~^~~~~~~~
foo.c:5:34: note: ‘change’ was declared here
    5 |         int year,month,day,sum=0,change,count;
      |                                  ^~~~~~