#include<stdio.h>
int main(){
      int x,y,z;
      scanf("%d%d%d",&x,&y,&z);
      if(x%2!=0 && y%2!=0 ||x%2==0 && y%2==0){
            printf("%d",z);
      }
      else if(x%2!=0 && z%2!=0 ||x%2==0 && z%2==0){
            printf("%d",y);
      }
      else if(y%2!=0 && z%2!=0 ||y%2!=0 && z%2==0){
            printf("%d",x);
      }

return 0;
}