Difficult to get up syndrome (bit by bit greed)

Title Description ：

Main idea ：

This topic mainly focuses on greed and bit operation .
a1=0:
After crossing the protective cover , The first i position =1, that ans Can directly +1<<i, No other conditions need to be met .
a2=0:
After crossing the protective cover , The first i position =1, Need to meet （1<<i)<=m, Because it needs to start x Of the i position =1.

#include<iostream>
#include<algorithm>
using namespace std;
int main()
{
    
    int n,m;
    cin>>n>>m;
    int a1=0,a2=-1;
    for(int i=1;i<=n;i++)
    {
    
        string op;
        int x;
        cin>>op>>x;
        if(op=="AND") a1&=x,a2&=x;
        if(op=="OR") a1|=x,a2|=x;
        if(op=="XOR") a1^=x,a2^=x;
    }
    int ans=0;
    for(int i=0;i<30;i++)
    {
    
        if(a1>>i&1) ans|=1<<i;
        else if(a2>>i&1)
        {
    
            if((1<<i)<=m)
            {
    
                ans|=1<<i;
                m-=1<<i;
            }
        }
    }
    cout<<ans<<endl;
    return 0;
}