foo.c: In function 'main':
foo.c:17:5: warning: unused variable 'md' [-Wunused-variable]
   17 | int md[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};
      |     ^~
foo.c:16:24: warning: unused variable 'i' [-Wunused-variable]
   16 | int year,month,day,sum,i;
      |                        ^
foo.c:16:20: warning: variable 'sum' set but not used [-Wunused-but-set-variable]
   16 | int year,month,day,sum,i;
      |                    ^~~
foo.c: At top level:
foo.c:22:1: error: expected identifier or '(' before 'if'
   22 | if(pd(year)==1)
      | ^~
foo.c:24:1: error: expected identifier or '(' before 'for'
   24 | for(i=1;i<month;i++)
      | ^~~
foo.c:24:10: error: expected '=', ',', ';', 'asm' or '__attribute__' before '<' token
   24 | for(i=1;i<month;i++)
      |          ^
foo.c:24:18: error: expected '=', ',', ';', 'asm' or '__attribute__' before '++' token
   24 | for(i=1;i<month;i++)
      |                  ^~
foo.c:27:1: warning: data definition has no type or storage class
   27 | sum=sum+day;
      | ^~~
foo.c:27:1: warning: type defaults to 'int' in declaration of 'sum' [-Wimplicit-int]
foo.c:27:9: error: 'day' undeclared here (not in a function)
   27 | sum=sum+day;
      |         ^~~
foo.c:29:8: error: expected declaration specifiers or '...' before string constant
   29 | printf("%d",sum);
      |        ^~~~
foo.c:29:13: error: expected declaration specifiers or '...' before 'sum'
   29 | printf("%d",sum);
      |             ^~~
foo.c:31:1: error: expected identifier or '(' before 'return'
   31 | return 0;
      | ^~~~~~
foo.c:33:1: error: expected identifier or '(' before '}' token
   33 | }
      | ^

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