编写取子字符串函数void fun(char s1[],char s2[],int m,int n...答:include<stdio.h> include<string.h> char *f(char *s,int m,int n);int main(void){ int m,n;char s1[20];printf("Please input m and n:");scanf("%d%d",&m,&n);printf("Please input a string:");scanf("%s",s1);printf("%s\n",f(s1,m,n));return 0;} char *f(...