CSP202012-2 期末预测之最佳阈值

#include<stdio.h>
#include<iostream>
#include<algorithm>
using namespace std;
const int m=100000;
struct node 
{
    int data, result, chance;
}student[m];
bool cmp(node a, node b)
{
    if (a.data == b.data)
    {
        return a.result > b.result;
    }
    else
    {
        return a.data < b.data;
    }
}
int main(void)
{
    int n;
    cin >> n;
    for (int i = 0; i < n; i++)
    {
        cin >> student[i].data >> student[i].result;
        student[i].chance = 0;
    }
    sort(student, student + n, cmp);
    //找出最大阈值准确率
    for (int i = 0; i < n - 1; i++)
    {
        if (student[i].result == 0)
        {
            student[n - 1].chance++;
        }
    }
    if (student[n - 1].result == 1)
    {
        student[n - 1].chance++;
    }
    //获取前一个阈值的准确率
    for (int i = n - 1; i >= 0; i--)
    {
        student[i].chance = student[i + 1].chance;
        if (student[i].result == 1)
        {
            student[i].chance++;
        }
        else
        {
            student[i].chance--;
        }
    }
    //去重
    for (int i = 0; i < n - 1; i++)
    {
        if (student[i].data == student[i + 1].data)
        {
            student[i + 1].chance = student[i].chance;
        }
    }
    //找到阈值
    int t = student[0].chance;
    int max;
    for (int i = 0; i < n; i++)
    {
        if (t <= student[i].chance)
        {
            t = student[i].chance;
            max = student[i].data;
        }
    }
    
        cout << max;
    return 0;
}    

参考：https://blog.csdn.net/weixin_45693289/article/details/115877445?utm_medium=distribute.pc_relevant.none-task-blog-2~default~baidujs_title~default-0.control&spm=1001.2101.3001.4242