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#include<stdio.h>
int main()
{
    long long i,j,k,l;
    long long n;
    scanf("%lld",&n);
    if(n==0)printf("0\n");else
    {
        j=1;
        k=9;
        while(n>j*k)
        {
            n=n-j*k;
            j++;
            k=k*10;
        }
        //printf("n=%lld\n",n);
        k=k/9;
        k=k+(n-1)/j;
        //printf("k=%lld\n",k);
        j=j-(n-1)%j;
        //printf("j=%lld\n",j);
        for(;j>0;j--)
        {
            l=k%10;
            k=k/10;
        }
        printf("%lld\n",l);
    }
    return 0;
}
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