Question

用C语言,编写一个名为fun的函数将字符串中所有的大写字母换成小写字母.高手来!

请尽量写的规范点,

Answer 1

#include <stdio.h>
#include <string.h>

void fun(char a[], int size)
{
int i;
for (i = 0; i < size; ++i)
{
if (a[i] >= 'A' && a[i] <= 'Z')
a[i] += 32;
}
}

void main()
{
char str[] = "This IS TEST!";
fun(str, strlen(str));
puts(str);
}

Answer 2

//任意字符串长度都行的,上面的却是固定的
//无用动态指针

#include <stdio.h>
void fun(char *q)
{
while(*q!='\0')
{
if (*q>= 'A'&&*q <= 'Z')
*q+= 32;
q++;
}
}

void main()
{
char *p;
p=new char;
printf("input string!:\n");
scanf("%s",p);
fun(p);
puts(p);
}

Answer 3

#include <stdio.h>
#include <ctype.h>

void fun(char *ch){
while(ch!=0){
ch=tolower(ch);
ch++;
}
}

int main(){
char ch[]= //添加你需要的字符串
fun(ch);
printf("%s",ch);
return 0;
}

Answer 4

fun(char *str)
{
while(str!=0)
toupper(str++);

}