如何在一堆数字中找出几个数，这几个数的和能够相加得一个固定值

Posted 2023-04-08

比如说，我有24个数，我要从里面找出4个，使得这4个数的值相加等于一个固定值（这个值我自己定）
如何编程？求高手！！！！！我把数字贴出来，能帮我做的就顺便啦，万分感谢！！！正确答案立马采纳！！
数值个数：25 要求找出4个，使得4个值相加等于5326.49
11.61

25.38

44.8

59.25

121.66

126.93

142.79

155.07

246.24

288.44

389.46

451.14

472.22

557.47

638.59

688.62

746.72

891.7

979.14

1028.66

1038.21

1153.38

1634.87

2760.68

In[6]:= a = 1161, 2538, 4480, 5925, 12166, 12693, 14279, 15507,
24624, 28844, 38946, 45114, 47222, 55747, 63859, 68862, 74672,
89170, 97914, 102866, 103821, 115338, 163487,
276068; mb = 487235; aa =
Table[ToExpression[StringJoin["a", ToString[i]]], i, 1, Length[a]];
bb = a.aa; t =
Solve[Flatten[Total[bb] == mb, Map[# >= 0, # <= 1 &, aa]], aa,
Integers]; Length[t]
aa /. t
Out[7]= 16
Out[8]= 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1,
1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1,
1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0,
0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0,
1, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1,
0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1,
0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0,
0, 1, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0,
0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0,
0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0,
1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1,
0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0,
0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0,
0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0,
1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0,
1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0,
0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,
0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0
用Mathematica解出来有16组解，如果是4张，那就是第一个解。运算过程中我把数据全放大了100倍，用整数来运算。 参考技术A 遍历即可，我用matlab编的简单程序，其他语言类似

A=[11.61,25.38,44.8,59.25, 121.66,126.93 ,142.79,155.07,246.24,288.44,389.46,451.14,472.22,557.47,638.59,688.62,746.72,891.7,979.14,1028.66,1038.21,1153.38,1634.87,2760.68];
n=length(A); %求A中元素的个数
for i=1:n-3
for j=i+1:n-2
for k=j+1:n-1
for l=k+1:n
if A(i)+A(j)+A(k)+A(l)==4872.35 %判断条件
[A(i) A(j) A(k) A(l)]
end
end
end
end
end

我这里预设的和是4872.35
程序运行的结果是44.8、1028.66、1038.21、2760.68
你要的和无解本回答被提问者采纳 参考技术B C++版代码如下，做了一点拓展，可以求出通解
#include<iostream>
#include<cstdio>
using namespace std;
double a[1000], b[1000], c[1000];
double x ;
int n,m ;

void f(int i, int l)
if(i > n || l > m) return;
b[l] = a[i];
c[l] = i ;

if(l == m)
double sum = 0;
for(int k = 1; k <= m; k++) sum += b[k];

if(sum == x)
for(int k = 1 ; k <= m ; k++)
cout << b[k];
if(k < m) cout << " + ";

cout << " = " << x << endl << "这是";
for(int k = 1 ; k <= m ; k++)
cout << "第 " << c[k] << " 个数" ;
if(k < m) cout << "、";

cout << "相加。" << endl;



else for(int y = i + 1; y <= n - m + l + 1 ; y ++) f(y, l+1);

return;


int main()
cout << "请输入数字个数（完成后回车）：";
cin >> n;

cout << "请输入这"<<n<<"个数，每输入一个间隔一个空格（所有数字都输入完成后回车）：\n" ;
for(int i = 1; i <= n ; i++) cin >> a[i];

cout <<"请输入需要选出多少个数相加（完成后回车）\n";
cout <<"（若需要的是选出任意个数的，请输入0然后回车）：\n";
cin >> m ;

cout << "请输入所需得到的固定值（完成后回车）：" ;
cin >> x ;

if(m == 0)
for(m = 1; m <= n; m++)
cout << "\n选出" << m << "个数相加，所得到的组合有：\n";
for(int i = 1; i <= n-m+1; i++) f(i,1);



else
cout << "\n选出" << m << "个数相加，所得到的组合有：\n";
for(int i = 1; i <= n-m+1; i++) f(i,1);


return 0;
参考技术C 你要的和不存在，。java版如下:

public class test

public static void main(String[] args)
Double[] d=11.61,25.38,44.8,59.25,121.66,126.93,142.79,155.07,246.24,288.44,389.46,451.14,472.22,557.47,638.59,688.62,746.72 , 891.7,979.14,1028.66,1038.21,1153.38,1634.87,2760.68;

double s=0.0;
int count=0;
double a=5560.54;
for(int i=0;i<24;i++)
for(int j=1;j<24;j++)
for(int x=2;x<24;x++)
for(int y=3;y<24;y++)
s=d[i]+d[j]+d[x]+d[y];

if(s==a)

System.out.print(d[i]+",");
System.out.print(d[j]+",");
System.out.print(d[x]+",");
System.out.println(d[y]);
System.out.println("------");


count=count+1;





System.out.println(count);

求一个数是几位数，并求每位数相加的和

//徐召阳 20163419 信1605-3
import java.util.ArrayList;
import java.util.Scanner;
public class Zhengshu
{
public static void main(String[] args)
{
System.out.print("请输入要计算的N");
Scanner scanner=new Scanner(System.in);
int number=scanner.nextInt();
scanner.close();
Zhengshu d=new Zhengshu(number);
d.qushu();
System.out.println(d.panduan()+"位数是");
for(int i=0;i<d.list.size();i++)
System.out.println(d.list.get(i));
System.out.println(d.panduan()+"位数字之和是"+d.add());
}
public ArrayList list = new ArrayList(0);//定义一个动态数组
int number;
public Zhengshu(int number)
{
this.number = number;
}
public int panduan()//位数的判断
{ int number1 = number;
int a=1;
while(number1/10!=0)
{
a=a+1;
number1=number1/10;
}
return a;
}
public void qushu()//各个位数的显示
{
int b=number;
while(b!=0)
{
list.add(b%10);
b=b/10;
}
}
public int add()//各个位数的相加
{
int c=0;
for(int i=0;i<list.size();i++)
{
c=c+(int)(list.get(i));
}
return c;
}
}