C语言程序设计教程（第三版）课后习题6.7 （C语言代码）

解题思路:





注意事项:





参考代码:

#include<stdio.h>
int main()
{
 int n=0,i=0,sum;
 int N;
 scanf( "%d", &N );
 for (n = 2; n < N; n++)
 {
  sum = 0;
  for (i = 1; i < n; i++)
  {
   if (n%i == 0)
   {
    sum += i;
   }
  }
  if (sum == n)
  {
   printf("%d its factors are ", n);
   for (i = 1; i < n; i++)
   {
    if (n%i == 0)
    {
     printf("%d ", i);
    }
   }
   printf("\n");
  }
 }
 return 0;
}

#include <stdio.h>
int main()
{
    double N, sum = 0;
 
    scanf( "%Lf", &N );
 
    for ( int i = 2; i <= N; i++ )
    {
        for ( int j = 1; j <=i/2; j++ )
 
        {
            if ( i % j == 0 )
            {
                sum = sum + j;
            }
        }
        if ( sum == i )
        {
            printf( "%d its factors are ", i );
 
            for ( int k = 1; k <=i/2; k++ )
            {
                if ( i % k == 0 )
                {
                    printf( "%d ", k );
                }
            }
            printf( "\n" );
        }
        sum = 0;
    }
    return 0;
}