#include <stdio.h>
#include <stdlib.h>
 
int myStrlen(char s[]){
    int i;
    for(i=0; s[i]!='\0' ;i++);
    return i;
}
 
int isPalindrome(char s[]){
    int i,j;
    for(i=0, j=myStrlen(s)-1; i<=j; i++, j--){
        if(s[i]!=s[j] && s[i]!='?' && s[j]!='?'){
        	return 0;
        }
    }
    return 1;
}
 
// 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;
	//以下に必要な宣言を含めて書いてください
	int i,j,num;
	num = myStrlen(s);
	tmp = (char *)malloc(sizeof(char)*(2*num+1));
	if(tmp == NULL){
        printf("error\n");
        return NULL;
    }
 
	for(i=0; i<num; i++){
		tmp[i] = s[i];
	}
	tmp[2*num] = '\0';
 
	int judge = isPalindrome(tmp);
	i = num - 1;
	while(judge==0 && i<2*num-1){
		i++;
		tmp[i] = '?';
		tmp[i+1] = '\0';
		judge = isPalindrome(tmp);
	}
 
	 while (j <= i) {
        if (tmp[i] == '?') {
            tmp[i--] = tmp[j++];
        } 
        else {
            break;
        }
    }
	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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