https://ac.nowcoder.com/acm/contest/317/A
题解:逆向模拟
/*
*@Author: STZG
*@Language: C++
*/
#include <bits/stdc++.h>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<string>
#include<vector>
#include<bitset>
#include<queue>
#include<deque>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
//#define DEBUG
#define RI register int
using namespace std;
typedef long long ll;
//typedef __int128 lll;
const int N=100000+10;
const int MOD=1e9+7;
const double PI = acos(-1.0);
const double EXP = 1E-8;
const int INF = 0x3f3f3f3f;
ll t,n,m,k,x,q;
ll ans,cnt,flag,temp;
ll a[N];
ll op[N];
char str;
int main()
{
#ifdef DEBUG
freopen("input.in", "r", stdin);
//freopen("output.out", "w", stdout);
#endif
scanf("%lld%lld",&n,&x);
for(int i=1;i<=n;i++){
scanf("%lld%lld",&op[i],&a[i]);
}
for(int i=n;i>=1;i--){
if(op[i]==1){
x-=a[i];
}else if(op[i]==2){
x+=a[i];
}else if(op[i]==3){
x/=a[i];
}else {
x*=a[i];
}
}
//scanf("%d",&t);
//while(t--){}
printf("%lld\n",x);
//cout << "Hello world!" << endl;
return 0;
}