编程马拉松 天仙配运行超时

import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner=new Scanner(System.in);
char c[][]=new char[10][10];
String string[]=new String[10];
int t=scanner.nextInt();

	while(t!=0){
		int n=t;
		int a[]=new int[2*n];
		int preSum[]=new int[2*n];
		int postSum[]=new int[2*n];
		int sum=0;
		for (int i = 0; i < a.length; i++) {
			a[i]=scanner.nextInt();
			sum+=a[i];
			preSum[i]=sum;
			//System.out.println("pre:"+preSum[i]);
		}
		sum=0;
		for (int i = 0; i < postSum.length; i++) {
			sum+=a[2*n-1-i];
			postSum[2*n-1-i]=sum;
			//System.out.println("post:"+postSum[2*n-1-i]);
		}
		int count=0;
		for(int i=0;i<2*n-1;i++){
			for (int j = i+1; j < 2*n; j++) {
				if (preSum[i]==postSum[j]) {
					count++;
					//System.out.println("1"+i+"   ;  "+" "+j);
				}
				if (preSum[j]==postSum[i]) {
					count++;
					//System.out.println("2"+i+"   ;  "+" "+j);
				}
			}
		}
		System.out.println(count);
		t=scanner.nextInt();
	}
}

}