谭浩强书本C语言代码第二章

#include <stdio.h>
void main()
{ 
   int i=2,t=1;
   while(i<=5)
{
          t=t*i;
  i++;
}
    printf("t=%d",t);
}

#include <stdio.h>
void main()
{ 
   int i=3,t=1;
   while(i<=11)
{
   t=t*i;
   i+=2;
}
   printf("t=%d",t);
}

#include <stdio.h>
void main()
{
  int i=1,g,n;
  while(i<=3)
       {

         scanf("%d,%d",&g,&n);
         if(g>=80)
         printf("g=%d,n=%d",g,n);
         i++;
       }
}


#include <stdio.h>
void main()
{ int i;
  for(i=2000;i<=2500;i++)
       {
        if((i%4==0&&i%100!=0)||(i%100==0&&i%400==0))
           printf("%d \n",i);   
        }
}

求1-1/2+1/3-1/4+――+1/99-1/100
#include <stdio.h>
void main()
{
  int i=2;
  float sum=1.0,sign=1.0,t;
  while(i<=100)
       {
         sign=-sign;
         t=sign*(1/i);
         sum+=t;
         i++;