#include<stdio.h>

int main(){
	int a[105], i=0, len=0, x;
	while( scanf("%d", &x) == 1){  
		if(x == 0){ 
			break;
		}
		else{
			a[i++] = x; 
			len += 1;   
		}
	}
	
	for(i=len-i;i>=0;i--){
        printf("%d",a[i]);
	}
	return 0;
}

https://www.luogu.com.cn/record/94267840