#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
char* setPalindrome(const char*s) {
    int len=strlen(s);
    char* palindrome=(char*)malloc((2*len+1)*sizeof(char));
    if(palindrome==NULL) {
        printf("メモリの確保に失敗しました。\n");
        return NULL;
    }
 
    strcpy(palindrome, s);
 
    for(int i=0;i<len;i++) {
        palindrome[len+i]=s[len-1-i];
    }
 
    palindrome[2*len]='\0';
 
    return palindrome;
}
 
int main() {
    char str[100];
    scanf("%99s",str);
 
    char*palindrome=setPalindrome(str);
    if(palindrome!=NULL) {
        printf("回文:%s\n",palindrome);
        free(palindrome);
    }
 
    return 0;
}
 

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