Educational Codeforces Round 27 D. Driving Test

单调栈

题意看了半天。。。

    #include <cstdio>
    #include <cstdlib>
    #include <cmath>
    #include <cstring>
    #include <string>
    #include <algorithm>
    #include <iostream>
    using namespace std;
    #define ll long long
     
    const int maxn=2e5+10;
    const int inf=1e9;
     
    int sum1,tot1;
    int f[maxn],g;
     
    int main()
    {
        int n,a,b,i,j,v;
        scanf("%d",&n);
        for (i=1;i<=n;i++)
        {
            scanf("%d",&a);
            if (a==1 || a==3)
                scanf("%d",&b);
     
            if (a==4)
                tot1=0;
            else if (a==6)
                tot1++;
            else if (a==2)
                sum1+=tot1,tot1=0;
     
            if (a==5)
                g=0;
            else if (a==1)
            {
                v=b;
                while (g>0 && f[g]<v)
                    g--,sum1++;
            }
            else if (a==3)
            {
                if (b<v)
                    sum1++;
                else
                    f[++g]=b;
            }
        }
        printf("%d",sum1);
        return 0;
    }