Sumsets

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 9983		Accepted: 2731

Description

Given S, a set of integers, find the largest d such that a + b + c = d where a, b, c, and d are distinct elements of S.

Input

Several S, each consisting of a line containing an integer 1 <= n <= 1000 indicating the number of elements in S, followed by the elements of S, one per line. Each element of S is a distinct integer between -536870912 and +536870911 inclusive. The last line of input contains 0.

Output

For each S, a single line containing d, or a single line containing "no solution".

Sample Input

52 3 5 7 1252 16 64 256 10240

Sample Output

12no solution

Source

 

转化成 a+b=c-d;

#include 
      
       #include 
       
        #define M 1010using namespace std;int num[M];int main(){    int n;    while(scanf("%d", &n) != EOF &&n!=0)    {        for(int i=0; i
        
         =0; i--)        {            for(int j=n-1; j>=0; j--)            {                if(i==j)                    continue;                int multiply=num[i]-num[j];                int rear=0, top= j-1;   //注意 top取值范围 ;                 while(rear
         
          num[rear]+num[top])                        rear++;                    if(multiply