foo.c: In function 'Is_Leap':
foo.c:6:11: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
    6 |         if(x%4==0)
      |           ^
foo.c: In function 'main':
foo.c:36:107: error: expected declaration specifiers or '...' before '(' token
   36 |     int d1=(year1/400-year2/400)*146097,d2=((year1-year1/400*400)/100-(year2-year2/400*400)/100)*36524,d3((year1-year1/100*100)/4-(year2-year2/100*100)/4)*1461,d4=((year1-year1/4*4)-(year2-year2/4*4))*365;
      |                                                                                                           ^
foo.c:37:18: error: 'd3' undeclared (first use in this function); did you mean 'd2'?
   37 |     total+=d1+d2+d3+d4+day1-day2;
      |                  ^~
      |                  d2
foo.c:37:18: note: each undeclared identifier is reported only once for each function it appears in
foo.c:37:21: error: 'd4' undeclared (first use in this function); did you mean 'd2'?
   37 |     total+=d1+d2+d3+d4+day1-day2;
      |                     ^~
      |                     d2
foo.c:38:12: warning: implicit declaration of function 'count' [-Wimplicit-function-declaration]
   38 |     total+=count(year1,month1)-count(year2,month2);
      |            ^~~~~
foo.c: In function 'diff':
foo.c:29:1: warning: control reaches end of non-void function [-Wreturn-type]
   29 | }
      | ^

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