#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[]){
    char *tmp;
    int i;
    int len = myStrlen(s); // 引数の「s」の長さを測る
 
    // 元の長さの2倍 + 終端文字(\0)分のメモリを確保
    tmp = (char *)malloc(sizeof(char) * (len * 2 + 1));
 
    if(tmp == NULL) return NULL; // エラーチェック
 
    for(i = 0; i < len; i++){
        tmp[i] = s[i];             // 前半：そのままコピー
        tmp[len * 2 - 1 - i] = s[i]; // 後半：逆順になるように配置
    }
 
    tmp[len * 2] = '\0'; // 最後に終端文字を入れる
    return tmp;          // 作った回文を返す
}
 
//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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