#include using namespace std; int main() {int N,M,i,j,aux,x,W=0,B=0; cin>>N>>M; int wi[N],bi[N]; for(i=0;i>wi[i]>>bi[i]; if(wi[i]+bi[i]!=M) return 0; } for(i=0;iwi[i]) { aux=wi[j]; wi[j]=wi[i]; wi[i]=aux; } } } for(i=0;ibi[i]) { aux=bi[j]; bi[j]=bi[i]; bi[i]=aux; } } } x=(N/2)-1; for(i=0;i<=x;i++) W=W+wi[i]; for(i=0;i<=x;i++) B=B+bi[i]; cout<