#include<stdio.h>
#include<string.h>
int main(){
    char num1[10],num2[10];
    int i,j,count;
    scanf("%s",&num1);
    scanf("%s",&num2);
    for(i=0;i<strlen(num1);i++){
        for(j=0;j<strlen(num2);j++){
            if(num1[i]==num2[j]){
                printf("%c",num[i]);
                count ++;
                break;
            }
        }
            if(count==0){
                printf("No common elements");
                return0;
            }
        
    }