#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で返します
char *setPalindrome(char s[]){
    char *tmp;
	int len = myStrlen(s);
    int i, j;
 
    tmp = (char *)malloc((2 * len + 1) * sizeof(char));
 
    for(i = 0; i < len; i++) {
        tmp[i] = s[i];
    }
 
    for(j = 0; j < len; j++) {
        tmp[i + j] = s[len - j - 1];
    }
 
    tmp[2 * len] = '\0';
    return tmp;
}
 
// メイン関数はいじる必要はありません
int main(){
    int i;
    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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