字符两个一组交换.c

include<stdio.h>

include<string.h>

int main()
{
char s[200];
fgets(s, sizeof(s), stdin);

int i,l;
l=strlen(s);

for(i=0;i<l;i+=2)
{
	
		printf("%c%c",s[i+1],s[i]);
		

}
return 0;

}