c - 需要显示多个数组中前3个最大的数字

Question

不知道如何找到前 3 个最大数字以及如何仅显示前 3 个最大数字

float feb10[] = { 25.0, 24.8, 24.8, 24.7, 25.1, 25.4, 25.1, 25.1, 25.0, 24.5, 24.3, 24.1 };

float feb11[] = { 23.8, 23.3, 22.9, 22.8, 22.9, 23.3, 23.1, 23.7, 23.0, 22.6, 22.9, 22.8 };

float feb12[] = { 22.8, 22.6, 22.8, 22.8, 24.2, 25.3, 24.8, 24.2, 24.2, 24.1, 24.7, 24.8 };

float feb13[] = { 24.9, 25.0, 24.9, 25.1, 25.4, 25.7, 25.9, 25.4, 25.1, 24.9, 25.2, 25.0 };

float feb14[] = { 25.0, 24.7, 24.6, 24.5, 25.3, 25.1, 25.2, 25.1, 24.9, 24.1, 24.1, 24.2 };

结果应该是

1st highest is 25.9

2nd highest is 25.7

joint 3rd highest is 25.4

Answer 1

我们初学者应该互相帮助。:)

完成该任务的一个简单方法是声明数组的数组。

还为三个最大元素声明一个数组。然后使用插入排序将当前最大的元素包含到最大元素数组中。

这是一个演示程序。

#include <stdio.h>

int main(void) 
{
    double feb10[] = { 25.0, 24.8, 24.8, 24.7, 25.1, 25.4, 25.1, 25.1, 25.0, 24.5, 24.3, 24.1 };
    double feb11[] = { 23.8, 23.3, 22.9, 22.8, 22.9, 23.3, 23.1, 23.7, 23.0, 22.6, 22.9, 22.8 };
    double feb12[] = { 22.8, 22.6, 22.8, 22.8, 24.2, 25.3, 24.8, 24.2, 24.2, 24.1, 24.7, 24.8 };
    double feb13[] = { 24.9, 25.0, 24.9, 25.1, 25.4, 25.7, 25.9, 25.4, 25.1, 24.9, 25.2, 25.0 };
    double feb14[] = { 25.0, 24.7, 24.6, 24.5, 25.3, 25.1, 25.2, 25.1, 24.9, 24.1, 24.1, 24.2 };

    double * a[] = { feb10, feb11, feb12, feb13, feb14 };
    const size_t M = sizeof( a ) / sizeof( *a );
    const size_t N = sizeof( feb10 ) / sizeof( *feb10 );

    enum { LARGEST_SIZE = 3 };  
    double max_values[LARGEST_SIZE] = { a[0][0] };
    size_t filled = 1;

    for ( size_t i = 0; i < M; i++ )
    {
        for ( size_t j = 0; j < N; j++ )
        {
            size_t pos = 0;
            while ( pos < filled && !( max_values[pos] < a[i][j] ) ) ++pos;

            if ( pos == filled )
            {
                // If the array of largest elements is not filled then
                // just append the array with the current largest element. 
                if ( filled != LARGEST_SIZE )
                {
                    max_values[filled++]  = a[i][j];
                }                   
            }
            else
            {
                // Here is used the insertion sort
                for ( size_t k = LARGEST_SIZE; --k != pos; ) max_values[k] = max_values[k-1];
                max_values[pos] = a[i][j];
            }
        }
    }

    for ( size_t i = 0; i < LARGEST_SIZE; i++ ) printf( "%.1f ", max_values[i] );
    putchar( '\n' );

    return 0;
}

它的输出是

25.9 25.7 25.4

看来您正在期待这个结果。:)