不知道为啥输出频率最高区间的几个数字不对

Question

#include<iostream>
using namespace std;
int main()
{
    int n;
    cin>>n;
    int b[1000]={0};
    for(int i=0;i<=n-1;i++)
        {cin>>b[i];}

    int a[5]={0};

    for(int i=0;i<=n-1;i++)
    { if(b[i]/10==10||b[i]/10==9) a[0]++;
    else if(b[i]/10==8)  a[1]++;
    else if(b[i]/10==7) a[2]++;
    else if(b[i]/10==6) a[3]++;
    else if(b[i]/10==5||b[i]/10==4||b[i]/10==3||b[i]/10==2||b[i]/10==1||b[i]/10==0) a[4]++;
    }
    for(int i=0;i<=4;i++)
       {if(i<=3)
           cout<<a[i];
           else cout<<a[i]<<'\n';
       }

     int maxa=0;
        for(int i=0;i<=4;i++)
        {
            maxa=max(maxa,a[i]);
        }
        cout<<maxa<<endl;

       if(maxa==0)
        {for(int i=0;i<=n-1;i++)
            {if(b[i]/10==10||b[i]/10==9) cout<<b[i];}
        }
       else if(maxa==1)
        {for(int i=0;i<=n-1;i++)
            {if(b[i]/10==8) cout<<b[i];}
        }
       else if(maxa==2)0
         {for(int i=0;i<=n-1;i++)
            {if(b[i]/10==7) cout<<b[i];}
        }
        else if(maxa==3)
        {for(int i=0;i<=n-1;i++)
            {if(b[i]/10==6) cout<<b[i];}
        }
        else if(maxa==4)
        {for(int i=0;i<=n-1;i++)
            {if(b[i]/10==5||b[i]/10==4||b[i]/10==3||b[i]/10==2||b[i]/10==1||b[i]/10==0) cout<<b[i];}
        }
}

为啥输出80的数字的时候输出不对 输出成60几了 是哪里有问题 代码要怎么改进

Answer 1

1、输出的第一行个数应该添加空格
2、最后一行是要输出分数最多的分数段的分数，你是直接用的最多的分段分数的个数来当下标了
3、最后一行输出是要按分数从高到低排序的，你没有排序
最后参考代码如下：

int main() {
    int n;
    cin >> n;
    int b[1000] = {0};
    for (int i = 0; i < n; i++) {
        cin >> b[i];
    }
    // 排序
    for (int i = 0; i < n - 1; i++) {
        for (int j = i + 1; j < n; j++) {
            if (b[i] < b[j]) {
                int t = b[i];
                b[i] = b[j];
                b[j] = t;
            }
        }
    }
    int a[5] = {0};
    for (int i = 0; i < n; i++) {
        if (b[i] >= 90 && b[i] <= 100) {
            a[0]++;
        } else if (b[i] >= 80 && b[i] < 90) {
            a[1]++;
        } else if (b[i] >= 70 && b[i] < 80) {
            a[2]++;
        } else if (b[i] >= 60 && b[i] < 70) {
            a[3]++;
        } else if (b[i] >= 0 && b[i] < 60) {
            a[4]++;
        }
    }
    int maxa = 0;
    int maxIndex = 0;
    for (int i = 0; i < 5; i++) {
        if (a[i] >= maxa) {
            maxa = a[i];
            maxIndex = i;
        }
        if (i == 4) {
            cout << a[i] << endl;
        } else {
            cout << a[i] << " ";
        }
    }
    cout << maxa << endl;
    // 找分数个数最多的分数段的下标的起始下标
    int startIndex = 0;
    for (int i = 0; i < maxIndex; i++) {
        startIndex += a[i];
    }
    for (int i = 0; i < maxa; i++) {
        if (i == maxa - 1) {
            cout << b[i + startIndex] << endl;
        } else {
            cout << b[i + startIndex] << " ";
        }
    }
    return 0;
}