示例：

/***  @brief how about recursive-forward-1? show you here.*  @author wen`xuanpei*  @email 15873152445@163.com(query for any question here)*/
#define _CRT_SECURE_NO_WARNINGS//support c-library in Microsoft-Visual-Studio
#include <stdio.h>static char *uint2rstr_nonzero(char *str, unsigned int ui){if(ui){*str++ = ui % 10 + '0';return uint2rstr_nonzero(str, ui / 10);}return str;
}
static char * uint2rstr(char *str, unsigned int ui){if( !ui )*str++ = '0';elsestr = uint2rstr_nonzero(str, ui);*str = '\0';return str;
}int main(){char str[20] = {};char *pt = NULL;pt = uint2rstr(str, 123U), printf("'%s', %d\n", str, pt - str);pt = uint2rstr(str, 0U), printf("'%s', %d\n", str, pt - str);getchar();return 0;
}

1）编译运行

2）要点分析

        1）在每一次函数调用层次增加之前做处理

        2）每一次处理，取得尾巴数字，输出到字符数组，从而得到逆序的字符串数字

尾声：

       其它不明白的地方不用过于纠结，那只是在浪费时间。学得多了，回过头来看自然融会贯通。