>>347
#include<stdio.h>
#define N 1000000
int main(void){
int min,max,mid;
int count1,count2;
int data,i;
FILE *fp;

fp=fopen("bdata.txt", "r");
if(fp==NULL) return 1;

count1=0;
while(fscanf(fp, "%d", &data)==1) count1+=data;

fclose(fp);

if(N%2) count2=(N+1)/2*N;
else count2=N/2*(N+1);

printf("%d\n", count2-count1);

return 0;
}