C语言判断字符串类型程序！！！！！！！！！！

#include <stdio.h>

int

main(int argc, char *argv[])

{

char str[101]={0}

char *p=str

int digitCount=0

int letterCount=0

printf("please input a string: ")

gets(str)

printf("your input string is: %s\n",str)

while(*p!='\0')

{

if(*p>'0'&&*p<'9')

{

digitCount++

}

else if((*p>'a'&&*p<'z')||(*p>'A'&&*p<'Z'))

{

letterCount++

}

p++

}

if(digitCount==0&&letterCount==0)

{

printf("you have nothing input.\n")

}

else if(digitCount>0&&letterCount>0)

{

printf("mixed\n")

}

else if(digitCount>0&&letterCount==0)

{

printf("digit\n")

}

else if(digitCount==0&&letterCount>=0)

{

printf("letter\n")

}

else

{

//no way

}

getchar()

return 0

}

#include<stdio.h>

#include<ctype.h>

#include<string.h>

main()

{

char a[10]int i,flag=1,dian=0,l

gets(a)

l=strlen(a)

if(a[0]!='-'&&!isdigit(a[0]))flag=0

for(i=1i<li++)

{

if(!isdigit(a[i])&&a[i]!='.')flag=0

if(a[i]=='.')dian++

}

if(dian>1)flag=0

if(flag==1){printf("yes!")getch()}

else exit(1)

}

水平有限,编了半个小时.没有辛劳也有疲劳

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