#include <stdio.h>
#include <cstring>
int a[1000001],d[17],add[17],b[1000001];
char nr1[1000001],nr2[20];
int main()
{
    freopen ("next.in","r",stdin);
    freopen ("next.out","w",stdout);
    scanf("%s",nr1);
    int s1=strlen(nr1)-1;
    for(int i=s1;i>=0;i--)
    {
        a[s1-i+1]=nr1[i]-'0';
        b[s1-i+1]=nr1[i]-'0';
    }
    scanf("%c",&nr1[0]);
    scanf("%s",nr2);
    int s2=strlen(nr2)-1;
    for(int i=s2;i>=0;i--)
    {
      d[s2-i+1]=nr2[i]-'0';
    }
    s2++;
    s1++;
    int stemp=s1;
    bool as=0;
    while(1)
    {
        if(s1<s2) break;
        else if(s1==s2)
        {
            for(int i=s2;i>=1;i--)
            {
                if(d[i]>b[i])
                {
                    as=1;
                    break;
                }
                else if(d[i]<b[i]) break;
            }
            if(as==1) break;
        }
        for(int i=1;i<=s2;i++)
        {
            b[i]-=d[i];
            if(b[i]<0)
            {
                b[i]+=10;
                b[i+1]--;
            }
        }
        for(int i=s2+1;i<=s1;i++)
        {
            if(b[i]<0)
            {
                b[i]+=10;
                b[i+1]--;
            }
            else break;
        }
        if(b[s1]==0) s1--;
    }
    for(int i=1;i<=s1;i++)
    {
        d[i]-=b[i];
        if(d[i]<0)
        {
            d[i]+=10;
            d[i+1]--;
        }
    }
    for(int i=s1+1;i<=s2;i++)
    {
        if(d[i]<0)
        {
            d[i]+=10;
            d[i+1]--;
        }
        else break;
    }
    while(d[s2]==0) s2--;
    s1=stemp;
    for(int i=1;i<=s1;i++)
    {
        a[i]+=d[i];
        a[i+1]+=a[i]/10;
        a[i]%=10;
    }
    if(a[s1+1]!=0) s1++;
    for(int i=s1;i>=1;i--) printf("%d",a[i]);
    printf("\n");
    return 0;
}