#include<iostream>
#include<cstring>
using namespace std;
string s1,s2;
string add(string s1,string s2){//加法
    long long a[10010]={},b[10010]={},c[10010]={};
    long long la=s1.length(),lb=s2.length(),lc=max(la,lb),x=0;
    string ans="";
    for(int i=0;i<la;i++)a[i]=s1[la-i-1]-'0';
    for(int i=0;i<lb;i++)b[i]=s2[lb-i-1]-'0';
    for(int i=0;i<lc;i++){
        c[i]=a[i]+b[i]+x;
        x=c[i]/10;
        c[i]=c[i]%10;
    }
    if(x)c[lc++]=1;
    for(int i=lc-1;i>=0;i--)ans+=(c[i]+'0');
    return ans;
}
string sub(string s1,string s2){//减法
    long long a[10010]={},b[10010]={},c[10010]={};
    long long la=s1.length(),lb=s2.length(),lc=max(la,lb),x=0,f=0;
    string ans="";
    if((s1 < s2 && s1.length() == s2.length()) || s1.length() < s2.length()){
        f=1;
        string t=s1;
        s1=s2;
        s2=t;
        swap(la,lb);
        cout<<'-';
    }
    for(int i=0;i<la;i++)a[i]=s1[la-i-1]-'0';
    for(int i=0;i<lb;i++)b[i]=s2[lb-i-1]-'0';
    for(int i=0;i<lc;i++){
        c[i]=a[i]-b[i]-x;
        if(c[i]<0){
            x=1;
            c[i]+=10;
        }else x=0;
    }
    while(c[lc-1]==0&&lc>1)lc--;
    for(int i=lc-1;i>=0;i--)ans+=(c[i]+'0');
    return ans;
}
string mul(string s1,string s2){//乘法
    long long a[10010]={},b[10010]={},c[20010]={};
    long long la=s1.length();
    long long lb=s2.length();
    long long lc=la+lb;
    string ans="";
    for(int i=0;i<la;i++) a[i]=s1[la-1-i]-'0';
    for(int i=0;i<lb;i++) b[i]=s2[lb-1-i]-'0';
    for(int i=0;i<la;i++){ 
        for(int j=0;j<lb;j++){
            c[i+j]+=a[i]*b[j];
            c[i+j+1]+=c[i+j]/10;
            c[i+j]%=10;
        }
    }
    while(c[lc-1]==0&&lc>1){
        lc--;
    }
    for(int i=lc-1;i>=0;i--) ans+=(c[i]+'0');
    return ans;
}
string div(string s,int b){//高精除低精
    int n,a[101000],c[101000],la,lc;
    la=s.length(),lc=0;
    for(int i=0;i<la;i++)a[i]=s[i]-'0';
    long long x=0;
    string ans="";
    for(int i=0;i<la;i++){
        c[i]=(x*10+a[i])/b;
        x=(x*10+a[i])%b;
    }
    while(c[lc]==0&&lc+1<la) lc++;
    for(int i=lc;i<la;i++)ans+=(c[i]+'0');
    return ans;
}
//高精除高精忒麻烦了懒得写
int main(){
	freopen("mark.in","r",stdin);
	freopen("mark.out","w",stdout);
    bool n1=0,n2=0;
	char f;
	cin>>f>>s1>>s2;
	if(s1[0]=='-'){s1.erase(0,1);n1=1;}
	if(s2[0]=='-'){s2.erase(0,1);n2=1;}
	if(f=='*'){if(n1+n2==1)cout<<"-";
	cout<<mul(s1,s2);}
	if(f=='+'){
	            if(n1==0&n2)cout<<sub(s1,s2);
	            else {if(n1+n2==2)cout<<"-";
	             cout<<add(s1,s2);
				}}
	if(f=='-'){ if(n1&&n2==0){cout<<"-"<<add(s1,s2);}
			        else if(n1&&n2)cout<<sub(s2,s1);
		                 else cout<<sub(s1,s2);}
	return 0;
}