#include<stdio.h>
#include<math.h>
int adad(char c ){
return ((int)c>=(int)'0' && (int)'9'>=(int)c);
}
int tabdil(char c){
return (int)c - (int)'0';
}
int main()
{
int x;scanf("%i\n",&x);
long long jam = 0;
long long jomle = 1;
int zarib = 1;
int tavan = 1;
while(1){
char c;scanf("%c",&c);
if(adad(c)){
zarib=tabdil(c);
while(1){
char r;scanf("%c",&r);
if(!adad(r)){
break;
}
zarib*=10;
zarib+=tabdil(r);
}
}
if(c=='x'){
scanf(" ^ %i",&tavan);
jomle *= zarib * pow(x,tavan);
}
if(c == '+' || c == '-'){
jam += jomle;
if( c == '-'){
jomle = -1;
}
else{
jomle = 1;
}
zarib = 1;
tavan = 1;
}
if(c=='\n'){
jam+=jomle;
break;
}
}
printf("%lli",jam);
}
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