判断集合S中是否含有两个元素其和为x

/*--------------判断集合S中是否含有两个元素其和为x---------------*/int judge(int a[],int n,int x){    merge_sort(a,0,n-1);    int i,j;    for(i=0,j=n-1;i<j;)    {        if(x>a[i]+a[j]) i++;        else if(x<a[i]+a[j]) j--;        else        {            printf("%d+%d = %d\n",a[i],a[j],x);            return 1;        }    }    printf("no such elements!\n");    return 0;}