#include <stdio.h>
#include <stdlib.h>
 
int myStrlen(char s[]){
    int i;
    for(i=0;s[i]!='\0';i++);
    return i;
}
 
// 関数の中でtmpに対してmallocして
// そこに回文を代入してreturnで返しましょう
char *setPalindrome(char s[]){
	int len = myStrlen(s);
    int palindrome_len = 2 * len;
	char *tmp =(char *)malloc((palindrome_len + 1) * sizeof(char));
 
for (int i = 0; i < len; i++) {
        tmp[i] = s[i];
    }
 
    for (int i = 0; i < len; i++) {
        tmp[len + i] = s[len - i - 1];
    }
 
    tmp[palindrome_len] = '\0';
    return tmp;
}
 
 
 
//メイン関数はいじる必要はありません
int main(){
    char nyuryoku[1024]; //入力
    char *kaibun;   //回文を受け取る
    scanf("%s",nyuryoku);
    kaibun = setPalindrome(nyuryoku);
    printf("%s\n -> %s\n",nyuryoku,kaibun);
    free(kaibun);
    return 0;
}

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