#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);
}