foo.c: In function 'main':
foo.c:6:13: error: expected expression before ':' token
    6 |         std::cin>>a>>b;
      |             ^
foo.c:7:12: error: expected '(' before 'a'
    7 |         if a%4==0,b==2;
      |            ^
      |            (
foo.c:7:12: warning: statement with no effect [-Wunused-value]
foo.c:8:24: error: expected ';' before 'if'
    8 |          printf("29/n")
      |                        ^
      |                        ;
    9 |           if b==1||b==3||b==5||b=7||b==8||b==10||b==12;
      |           ~~            
foo.c:10:26: error: expected ';' before 'if'
   10 |            printf("31/n")
      |                          ^
      |                          ;
   11 |                  if b==4||b==6||b==9||b==11;
      |                  ~~       
foo.c:12:30: error: expected ';' at end of input
   12 |                printf("30/n")
      |                              ^
      |                              ;
   13 | 
foo.c:12:16: error: expected declaration or statement at end of input
   12 |                printf("30/n")
      |                ^~~~~~
foo.c:6:9: warning: label 'std' defined but not used [-Wunused-label]
    6 |         std::cin>>a>>b;
      |         ^~~
foo.c:5:8: warning: unused variable 'b' [-Wunused-variable]
    5 |  int a,b;
      |        ^

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