算法之递归-数组分组

 

#include<iostream>
#include<vector>
#include<math.h>
using namespace std;
vector<int> elsevec;
int n,m,sum3,sum5,dis0; 
bool f(int i,int dis){
    if(i==elsevec.size()){
        return abs(dis)==dis0;
    }return (f(i+1,dis+elsevec[i])||f(i+1,dis-elsevec[i])); //**重点**
}
int main(){
    while(cin>>n){
        sum3=sum5=0;
        elsevec.clear();
        int t=n;
        while(t--){
            cin>>m;
            if(m%5==0){
                sum5+=m;    
            }else if(m%3==0){
                sum3+=m;
            }else{
                elsevec.push_back(m);
            }
        }dis0=abs(sum5-sum3);    
        if(f(0,0)){
            cout<<"true"<<endl;
        }else cout<<"false"<<endl;
    }
    return 0;
}