C 为什么printf不只打印ini字符串？

我需要将“ini”字符串复制到“final”字符串，反转字符顺序，但当我打印字符串“ini”时，它似乎同时打印“ini”和“final”

语言：C

#include <stdio.h>

void main(){
    char ini[10]={'a','b','c','d','e','f','g','h','i','j'};
    char final[10];

    for (int i = 0; i < 10 ; i++) {
        final[i]=ini[10-1-i];
    }
    printf("%s\n\n",ini);
    printf("%s",final);
}

但应该是这样的：

abcdefghij

jihgfedcba

---

字符串需要空终止符

#include <stdio.h>

void main(){
    char ini[11]={'a','b','c','d','e','f','g','h','i','j', 0};
    char final[11];

    for (int i = 0; i < 10 ; i++) {
        final[i]=ini[10-1-i];
    }
    final[10] = 0;
    printf("%s\n\n",ini);
    printf("%s",final);
}

#include <stdio.h>

void main(){
    char ini[11]={'a','b','c','d','e','f','g','h','i','j', 0};
    char final[11];

    for (int i = 0; i < 10 ; i++) {
        final[i]=ini[10-1-i];
    }
    final[10] = 0;
    printf("%s\n\n",ini);
    printf("%s",final);
}

char ini[] = "abcdefghij";