#include<iostream>#include<cstdio>#include<cstring>#include<string>#include<algorithm>#include<map>#include<queue>#include<stack>#include<cmath>#include<vector>#define inf 0x3f3f3f3f#define Inf 0x3FFFFFFFFFFFFFFFLL#define eps 1e-9#define pi acos(-1.0)using namespace std;typedef long long ll;const int maxn=1000+10;const int maxm=200000+10;struct Edge{ int to,cap,flow,next; Edge(){} Edge(int to,int cap,int flow,int next):to(to),cap(cap),flow(flow),next(next){}}edges[maxm<<1];int head[maxn],d[maxn],cur[maxn],nEdge;void AddEdges(int from,int to,int cap){ edges[++nEdge]=Edge(to,cap,0,head[from]); head[from]=nEdge; edges[++nEdge]=Edge(from,0,0,head[to]); head[to]=nEdge;}bool BFS(int s,int t){ memset(d,0xff,sizeof(d)); d[s]=0; queue<int>q; q.push(s); while(!q.empty()) { int u=q.front();q.pop(); for(int k=head[u];k!=-1;k=edges[k].next) { Edge e=edges[k]; if(d[e.to]==-1&&e.cap>e.flow) { d[e.to]=d[u]+1; q.push(e.to); } } } return d[t]!=-1;}ll DFS(int u,int a,int t){ if(u==t||a==0) return a; ll flow=0; int f; for(int &k=cur[u];k!=-1;k=edges[k].next) { Edge e=edges[k]; if(d[e.to]==d[u]+1&&(f=DFS(e.to,min(a,e.cap-e.flow),t))>0) { edges[k].flow+=f; edges[k^1].flow-=f; flow+=f;a-=f; if(a==0) break; } } return flow;}ll MaxFlow(int s,int t){ ll flow=0; while(BFS(s,t)) { for(int i=0;i<=t;++i) cur[i]=head[i]; flow+=DFS(s,inf,t); } return flow;}int val[maxn],xval[maxn];vector<int>L,R;ll gcd(ll a,ll b){ ll c; while(b) { c=a%b; a=b; b=c; } return a;}int main(){ int n,p; while(~scanf("%d%d",&n,&p)) { memset(head,0xff,sizeof(head)); nEdge=-1; L.clear();R.clear(); int x,y,S=0,T=n+1; ll sum=0; for(int i=1;i<=n;++i) { scanf("%d%d",&x,&y); if((x^y)&1) L.push_back(i); else R.push_back(i); val[i]=(x&y); xval[i]=(x^y); sum+=val[i]; } for(int i=0;i<(int)L.size();++i) for(int j=0;j<(int)R.size();++j) { if(gcd(xval[L[i]]^xval[R[j]],p)<=1) AddEdges(L[i],R[j],inf); } for(int i=0;i<(int)L.size();++i) AddEdges(S,L[i],val[L[i]]); for(int i=0;i<(int)R.size();++i) AddEdges(R[i],T,val[R[i]]); ll ans=sum-MaxFlow(S,T); printf("%lldn",ans); } return 0;}
