foo.c: In function 'pd':
foo.c:5:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    5 |         if(y%4==0&&y%100!=0||y%400==0)
      |            ~~~~~~^~~~~~~~~~
foo.c: In function 'main':
foo.c:17:15: warning: statement with no effect [-Wunused-value]
   17 |         arr[2]==29;
      |         ~~~~~~^~~~
foo.c:13:22: warning: 'sum' may be used uninitialized [-Wmaybe-uninitialized]
   13 |         int y, m, d, sum, i;
      |                      ^~~

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