Answer:
C++:
C++ Code:
#include <iostream>
#include <string>
using namespace std;
struct date
{
   int d,m,y;
};
int isLeap(int y)
{
   if(y%100==0)
   {
       if(y%400==0)
       return 1;
       return 0;
   }
   if(y%4==0)
   return 1;
   return 0;
}
int day_no(date D)
{
   int m = D.m;
   int y = D.y;
   int d = D.d;
   int i;
   int mn[13] = {0,31,28,31,30,31,30,31,31,30,31,30,31};
   for(i=0;i<m;i++)
   {
       d += mn[i];
   }
   if(isLeap(y))
   {
       if(m>2)
       d++;
   }
   return d;
}
date get_info(string s)
{
   date D;
   int i,p1,p2,l = s.length();
   for(i=0;i<l;i++)
   {
       if(s[i] == '-')
       {
       p1 = i;
       break ;
       }
   }
   for(i=p1+1;i<l;i++)
   {
       if(s[i] == '-')
       {
       p2 = i;
       break ;
       }
   }
  
   D.m = 0;
   for(i=0;i<p1;i++)
   D.m = (D.m)*10 + (s[i]-'0');
  
   D.d = 0;
   for(i=p1+1;i<p2;i++)
   D.d = (D.d)*10 + (s[i]-'0');
  
   D.y = 0;
   for(i=p2+1;i<l;i++)
   D.y = (D.y)*10 + (s[i]-'0');
  
   return D;
  
}
int main()
{
   string s1 = "4-5-2008";
   string s2 = "12-30-1995";
   string s3 = "6-21-2000";
   string s4 = "1-31-1500";
   string s5 = "7-19-1983";
   string s6 = "2-29-1976";
  
   cout<<"Date\t\tDay no\n\n";
   cout<<s1<<"\t"<<day_no(get_info(s1))<<endl;
   cout<<s2<<"\t"<<day_no(get_info(s2))<<endl;
   cout<<s3<<"\t"<<day_no(get_info(s3))<<endl;
   cout<<s4<<"\t"<<day_no(get_info(s4))<<endl;
   cout<<s5<<"\t"<<day_no(get_info(s5))<<endl;
   cout<<s6<<"\t"<<day_no(get_info(s6))<<endl;
  
  
   return 0;
}
Explanation: