UVA - 442

//stack处理公式串#include<iostream>#include<cstdio>#include<sstream>#include<cmath>#include<cstring>#include<cctype>#include<algorithm>#include<vector>#include<set>#include<map>#include<queue>#include<deque>#include<stack>using namespace std;const int maxn=30;struct nod{    long long a,b;}p[maxn];nod mk(int x,int y){    nod n;    n.a=x,n.b=y;    return n;}stack<nod> stk;void init(){    while(!stk.empty())        stk.pop();}int main(){    int T;    cin>>T;    char chr;    string s;    while(T--){        cin>>chr;        cin>>p[chr-'A'].a>>p[chr-'A'].b;    }    getchar();    while(getline(cin,s)){        init();        long long ans=0;        int jud=0;        for(int i=0;i<s.size();i++){            if(isalpha(s[i]))                stk.push(p[s[i]-'A']);            if(s[i]==')'){                nod n1=stk.top();stk.pop();                nod n2=stk.top();stk.pop();                if(n1.a!=n2.b){                    jud=1;                    cout<<"error"<<endl;                    break;                }                else{                    stk.push(mk(n2.a,n1.b));                    ans+=n2.a*n2.b*n1.b;                }            }        }        if(!jud)            cout<<ans<<endl;    }    return 0;}