Bit computing + thinking Codeforces Round # 630 (Div. 2) D title Walk on Matrix

Walk on Matrix

Subject to the effect that:

To give you a positive integer k, let you design a n * m board, each board has a point value, you just start at (1,1) point, your goal is to come (n, m) point, and to obtain a maximum priority value, the weight value calculation formula as dp [i] [j] = max (dp [i-1] [j] & a [i] [j], dp [i] [j-1] & a [i] [j]);

Dp clear that this applies only to conventional operation, bit operation is not applicable;

So you entitled to k, let you design chessboard, so that the maximum value of the dp operation, with the difference between the actual maximum value of k;

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Others looked at the code and found that only 3 lines;

Thinking this problem is to construct dp out value is 0, the actual value of k, this comparison really want, the basic idea of ​​the structure;

But how construction is more difficult, and there is no good explanation;

On the four formulas:

k&k=k,x&k=0,(x+k)&k=k,(x+k)&x=x；

Directly on the code:

#include<bits/stdc++.h>
#define LL long long
#define pa pair<int,int>
#define ls k<<1
#define rs k<<1|1
#define inf 0x3f3f3f3f
using namespace std;
const int N=510;
const int M=1010;
const LL mod=1e8-3;
int main(){
	int k;
	cin>>k;
	int x=(1<<17);
	cout<<2<<" "<<3<<endl;
	cout<<x+k<<" "<<x<<" "<<0<<endl;
	cout<<k<<" "<<x+k<<" "<<k<<endl; 
	return 0;
}