练习2-1
#include<stdio.h>
#include<limits.h>
int main()
{
printf("signed char min:%d , max:%d\n", SCHAR_MIN, SCHAR_MAX);
printf("unsigned char min:%d , max:%u\n",0,UCHAR_MAX);
printf("short min:%d , max:%d\n", SHRT_MIN, SHRT_MAX);
printf("unsigned short min:%d , max:%u\n",0, USHRT_MAX);
printf("int min:%d , max:%d\n", INT_MIN, INT_MAX);
printf("unsigned int min:%d , max:%u\n", 0, UINT_MAX);
printf("long min:%ld , max:%ld\n", LONG_MIN, LONG_MAX);
printf("unsigned long min:%d , max:%lu\n", 0, ULONG_MAX);
return 0;
}

练习2-2
i=0;
while(i<(lim-1)){
c=getchar();
if(c=='\n')
break;
else if(c==EOF)
break;
++i;
s[i]=c;