foo.c: In function 'main':
foo.c:6:3: error: expected ',' or ';' before 'scanf'
   scanf("%d %d %d",&y,&m,&d)
   ^~~~~
foo.c:5:8: warning: unused variable 'mon' [-Wunused-variable]
    int mon[]={31,28,31,30,31,30,31,31,30,31,30,31}
        ^~~
foo.c:4:15: warning: unused variable 'b' [-Wunused-variable]
 { int y,m,d,a,b;
               ^
foo.c:4:13: warning: unused variable 'a' [-Wunused-variable]
 { int y,m,d,a,b;
             ^
foo.c:4:11: warning: unused variable 'd' [-Wunused-variable]
 { int y,m,d,a,b;
           ^
foo.c:4:9: warning: unused variable 'm' [-Wunused-variable]
 { int y,m,d,a,b;
         ^
foo.c:4:7: warning: unused variable 'y' [-Wunused-variable]
 { int y,m,d,a,b;
       ^

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