Luogu2114 [NOI2014]起床困难综合症 【位运算】
题目分析：
按位处理即可
代码：
1 #include<bits/stdc++.h> 2 using namespace std; 3 4 const int maxn = 105000; 5 6 int n,m; 7 int a[maxn],b[maxn]; 8 9 void work(){ 10 int z = 0; 11 for(int i=29;i>=0;i--){ 12 if((1<<i)+z > m)continue; 13 int l = (1<<i),r=0; 14 for(int i=1;i<=n;i++){ 15 if(a[i] == 0) l = (l&b[i]),r = (r&b[i]); 16 else if(a[i] == 1) l = (l|b[i]),r = (r|b[i]); 17 else l = (l^b[i]),r = (r^b[i]); 18 } 19 if((r&(1<<i)) != 0) continue; 20 if((l&(1<<i)) == 0) continue; 21 z += (1<<i); 22 } 23 for(int i=1;i<=n;i++){ 24 if(a[i] == 0) z = (z&b[i]); 25 else if(a[i] == 1) z= (z|b[i]); 26 else z = (z^b[i]); 27 } 28 printf("%d\n",z); 29 } 30 31 int main(){ 32 scanf("%d%d",&n,&m); 33 for(int i=1;i<=n;i++){ 34 char ch = getchar(); 35 while(ch > 'Z' || ch < 'A') ch = getchar(); 36 if(ch == 'A'){a[i] = 0;} 37 else if(ch == 'O'){a[i] = 1;} 38 else a[i] = 2; 39 while(ch != ' ') ch = getchar(); 40 scanf("%d",&b[i]); 41 } 42 work(); 43 return 0; 44 }
