#include<stdio.h>
#include<string.h>
int main(void){
   int N,a[4000],big=0,x,tmp,r,w,b,i=0,mod;
   scanf("%d",&N);
   for(i=0;i<N;i++){
      scanf("%d",&a[i]);
      mod+=a[i]-1;
         }
  pritf("%d",mod);

   return 0;
}
