编程实现删除字符串中所有指定的字符

问题
假设字符串为“cabcdefcgchci”,把该字符串中所有的字符‘c’删除后，结果为“abdefghi”.
代码

#include <stdio.h>char *deleteChar(char *str，char c){    char *head = NULL;    char *p = NULL;    if(str ==NULL)    {        return NULL;    }    head = p = str;    while(*p++)    {        if(*p != c)        {            *str++ = *p;        }    }    *str = '\0';    return head;}int main(){    char string[] = "cabcdefcgchci";    char c = 0;    scanf("%c",&c);    printf("%s\n",string);    deleteChar(string,c);    printf("%s\n",string); //abdefghi    return 0;}