delete pics to save space

p.CH1602.cpp

@@ -0,0 +1,42 @@
+//http://contest-hunter.org:83/contest/0x10%E3%80%8C%E5%9F%BA%E6%9C%AC%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84%E3%80%8D%E4%BE%8B%E9%A2%98/1602%20The%20XOR%20Largest%20Pair
+#include<cstdio>
+#include<cstring>
+#include<algorithm>
+using namespace std;
+const int maxmem=1e5*32+5;
+const int maxn=1e5+5;
+int n,a[maxn],G[maxmem][2],cnt;
+inline void insert(int x)
+{
+	int p=0;
+	for(int i=30;i>=0;i--)
+	{
+		int now=(x>>i)&1;
+		if(!G[p][now]) G[p][now]=++cnt;
+		p=G[p][now];
+	}
+}
+inline int query(int x)
+{
+	int p=0,res=0;
+	for(int i=30;i>=0;i--)
+	{
+		int now=(x>>i)&1;
+		if(G[p][now^1]) { p=G[p][now^1]; res+=1<<i; }
+		else p=G[p][now];
+	}
+	return res;
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d",&n);
+	for(int i=0;i<n;i++) scanf("%d",&a[i]);
+	for(int i=0;i<n;i++) insert(a[i]);
+	int res=0;
+	for(int i=0;i<n;i++) res=max(res,query(a[i]));
+	printf("%d\n",res);
+	return 0;
+}