题意：Give you three sequences of numbers A, B, C, then we give you a number X. Now you need to calculate if you can find the three numbers Ai, Bj, Ck, which satisfy the formula Ai+Bj+Ck = X.

即给出一个A数组，B数组，C数组，和S个询问，每个询问给出一个X值，问是否存在符合条件的等式。

分析：可以用hash存下a数组和b数组中所有元素的和，然后可以用hash或者二分的方法查找是否存在x-ck即可。

#include 
      
       #include 
       
        #include 
        
         using namespace std;const int maxn = 505;const int mod = 600000;const int INF = (1<<30);struct node{    int key;    int count;}h[mod];int a[maxn];int b[maxn];int c[maxn];void add(int p){    int k = p%mod;    if (k < 0)        k += mod;    while (h[k].count != 0)    {        if (h[k].key == p)        {            h[k].count++;            break;        }        k = (k+1)%mod;    }    if (h[k].count == 0)    {        h[k].count++;        h[k].key = p;    }}bool find(int p){    int k = p%mod;     if (k < 0)        k += mod;    while (h[k].count!=0)    {        if (h[k].key == p)            return true;        k = (k+1)%mod;    }    return false;}int main(){    int i, j,k;    int l, n, m, s;    int p;    int ca = 1;    while (scanf("%d %d %d",&l,&m,&n)!=EOF)    {          memset(h,0,sizeof(h));          for (i=0; i
         
          p || a[l-1]+b[m-1]+c[n-1]