#include<stdio.h> #include<stdlib.h> #include<string.h> #define?da?100 int?add(char?*p){ ????????p=(char*)malloc(da*sizeof(char)); ????????scanf("%100s",p); ????????int?size=strlen(p); ????????if(size==da) ????????p=(char*)realloc(p,(da+10)*sizeof(char)); ????????return?0; } int?main(void){ ????????char?*p,*t; ????????int?size,nbytes; ????????add(p); ????????add(t); ????????size=strlen(p); ????????nbytes=strlen(t); ????????if(size!=nbytes){ ????????printf("兩次數據大小不一\n"); ????????return?-1; } ????????printf("%d\n",size); ????????printf("%s\n",p); ????????printf("%c\n",p[1]); ????????free(p); ????????free(t); ????????return?0; }這些代碼編譯通過，但是運行時? 輸入完字符串以后會提示段錯誤，? 如果去掉add函數，把add里的東西都放到main里? 程序編譯完后正常運行，，這是為啥? 指針要怎么傳入