6.1找出两个字符串第一个相同的字符

#include <stdio.h>char *find_char( char const *source, char const *chars );void main(){char source[20],chars[20];char *p;gets(source);gets(chars); p = find_char(source, chars); if ( p != NULL ) printf("%c/n",*p);elseprintf("don't find/n");}char *find_char( char const *source, char const *chars ){int i;char *p;for (i=0; *(source+i)!='/0'&&*(chars+i)!='/0'; i++)if ( *(source+i)==*(chars+i) ){p = source+i;break;}if ( *(source+i)=='/0' || *(chars+i)=='/0' )p = NULL;return(p);}