#include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int main(){ char s1[151],s2[151]; cin>>s1>>s2; int s1_num=0,s2_num=0; int i=0 while(s1[i]!='\0'){ s1_num++; i++; } while(s2[i]!='\0'){ s2_num++; i++; } if(s1_num==s2_num){ cout<<"yes"<<endl; } else cout<<"no"<<endl; return 0; }