洛谷P3952 时间复杂度

非常繁琐，细节巨多。
1.尤其注意两个n出现时按常数算。
2.读入数字时要读整个字符串，而不是单个字符

#include<cstring>
#include<algorithm>
#include<stack>
#include<cstdio>
#include<iostream>
using namespace std;
const int inf = 100000 + 3;
int check[200];
inline int get(char a){  return (int)a; }
inline int exchange(char h[])
{
    if(h[0] == 'n')return inf;
    else 
    {
        int num = 0, cnt = 0;
        while(h[cnt] >= '0' && h[cnt] <= '9')
        {
            num = num * 10 + h[cnt] - '0';
            ++cnt;
        }
        return num;
    }
}
struct Node
{
    int skip, comp, idx;        
    Node(int skip = 0,int comp = 0,int idx = 0):skip(skip), comp(comp), idx(idx){}
};
stack<Node>S;
int main()
{
    //freopen("f.txt","r",stdin);
    int T;
    scanf("%d",&T);
    char h[10];
    char s[20];
    while(T--)
    {
        while(!S.empty()) S.pop();
        memset(check,0,sizeof(check));
        int n;
        int  flag = 1, ans = 0;
        scanf("%d",&n);
        scanf("%s",s);
        for(int i = 1;i <= n;++i)
        {
            scanf("%s",h);
            if(h[0] == 'E')
            {
                if(S.empty()) {flag = 0;}
                else 
                {
                    Node u = S.top();
                    check[u.idx] = 0;
                    ans = max(ans,u.comp);
                    S.pop();
                }
                continue;
            }
            Node new_node;
            scanf("%s",h);
            int id = get(h[0]), num1, num2, cm = 0;
            if(check[id]) {flag = 0;}
            check[id] = 1;
            scanf("%s",h);  num1 = exchange(h);
            scanf("%s",h);  num2 = exchange(h);
            cm = (!S.empty()) ? S.top().comp : 0;
         //  printf("%d %d\n",num1,num2);
            if(num1 > num2) S.push(Node(1,0,id));
            else 
            {
                if(!S.empty() && S.top().skip == 1)S.push(Node(1,0,id));
                else
                {
                    if(num2 == inf && num1 != inf) ++cm;
                    ans = max(ans,cm);
                    S.push(Node(0,cm,id));
                } 
            }
        }
        if(flag == 0 || !S.empty()) printf("ERR\n");
        else
        {
            if(s[2] - '0' == 1)
            {
                if(ans == 0) printf("Yes\n");
                else printf("No\n");
            } 
            else
            {
                int num = 0, cnt = 4;
                while(s[cnt] >= '0' && s[cnt] <= '9')
                {
                    num = num * 10 + s[cnt] - '0';
                    ++cnt;
                }
                if(num == ans) printf("Yes\n");
                else printf("No\n");
            }
        }
    }
    return 0;
}