#include <bits/stdc++.h> using namespace std; const int maxn = 100; char mass[maxn]="1100"; char x[maxn]="1011"; char tmp[maxn]; int main() { // scanf("") // mass = "1100"; // x = "1011"; int lenx = strlen(x); int lenmass = strlen(mass); int i,j,k; for(i = 0; i < lenx-1; i++) mass[i+lenmass] = '0'; lenmass += (lenx-1); for(i = lenx-1; i < lenmass; i++) { memset(tmp,0,sizeof(tmp)); for(j = i-lenx+1,k=0; j <= i; j++,k++) tmp[k] = mass[j]; if(tmp[0]=='0') continue; else { for(j = i-lenx+1,k=0; j<= i; j++,k++) { mass[j] = (x[k]-'0')^(tmp[k]-'0')+'0'; } } } for(i = lenmass-lenx+1; i < lenmass; i++) printf("%c",mass[i]); puts(""); return 0; }