起床困难综合症题解

链接：登录—专业IT笔试面试备考平台_牛客网
来源：牛客网

位运算，菜，好像明白好像不明白QAQ

AC代码：

#include 
using namespace std;
int n,m;
pair a[100005];
int calc(int bit,int now){
    for(int i = 1;i <= n;i++){
        int x = a[i].second >> bit & 1;
        if(a[i].first == "AND") now &= x;
        else if(a[i].first == "OR") now |= x;
        else now ^= x;
    }
    return now;
}
int main(){
    cin >> n >> m;
    for(int i = 1;i <= n;i++){
        char str[5];
        int x;
        scanf("%s%d",str,&x);
        a[i] = make_pair(str,x);
    }
    int val = 0,ans = 0;
    for(int bit = 29;bit >= 0;bit--){
        int res0 = calc(bit,0);
        int res1 = calc(bit,1);
        if(val + (1 << bit) <= m && res0 < res1){
            val += 1 << bit,ans += res1 << bit;
        }else{
            ans += res0 << bit;
        }
    }
    cout << ans << 'n';
    return 0;
}