题解 | #统计成绩#

#include <stdio.h>
#include<stdlib.h>
void print(float arr[], int org_length, float avg) {
    printf("%.2f %.2f %.2f", arr[org_length - 1], arr[0], avg);
}

void swap(float arr[], int i, int j) {
    float tmp = arr[i];
    arr[i] = arr[j];
    arr[j] = tmp;
}

void selectionSort(float arr[], int length) {

    int orig_length = length;

    if (NULL == arr || length < 2) {
        return;
    }

    int minIndex = 0;
    int maxIndex = 0;
    //冒泡排序
    /* for(int end=length-1; end>0;end--)
    {
        for(int i=0;i<end;i++)
        {
            if(arr[i]>arr[i+1])
            {
                swap(arr,i,i+1);
            }
        }
    }*/
    /*选择排序
    for (int i = 0; i < length - 1; i++) {
        minIndex = i;
        for (int j = i + 1; j < length; j++) {
            if (arr[j] < arr[minIndex]) {
                minIndex = j;
            }
        }
        swap(arr, i, minIndex);
    }
    *///插入排序

    for(int i=0;i<length;i++)
    {
        for(int j=i-1;j>=0 && arr[j]> arr[j+1] ;j--)
        {
            swap(arr,j,j+1);
        }
    }
    float sum = 0.0;

    for (int i = 0; i < orig_length; i++) {
        sum += arr[i];
    }

    float avg = sum / orig_length;

    print(arr, orig_length, avg);

}

int main() {

    float* arr;
    int n = 0;

    scanf("%d", &n);
    arr = (float*)realloc(NULL, n * sizeof(float));
    for (int i = 0; i < n; i++) {
        scanf("%f", &arr[i]);
    }

    selectionSort(arr, n);
    arr = NULL;
    return 0;

}