关于字符串操作

#include <stdio.h>#include <string.h># include <stdlib.h>int main(){    char row[15]="00121212345678";    char oilgunno[20] = "9898";    char sql[24];    char auth_seq[16];    int i,authno;    /*数组的初始化*/    memset (sql, '0', sizeof(sql));    memset (auth_seq, '0', sizeof(auth_seq));    strcpy(sql,row);    for(i = 4;i < 12;i++ ){        auth_seq[i-4] = sql[i];    }    /*省去前4位取中间的8位复制给auth_seq*/    auth_seq[i-4] = '\0';    /*此时在字符串的后面加上'\0'变成字符串*/    printf("auth_seq=%s\n",auth_seq);    authno = atoi(auth_seq)+1;    printf("authno=%d\n",authno);    /*itoa(authno, auth_seq, 10);*/    sprintf(auth_seq,"%d",authno);    printf("auth_seq=%s\n",auth_seq);    strcat(oilgunno,auth_seq);    printf("oligunno=%s\n",oilgunno);       return 0;}运行结果：jiangxianxd@jiangxianxd:~/text$ ./opstring auth_seq=12123456authno=12123457auth_seq=12123457oligunno=989812123457