ll@N,@M,@A[N][3];vector<double>B[N],X[M+1];
rep(i,N)B[i]={(1.0/A[i][0]-1.0/A[i][1])/A[i][2],1.0/A[i][0],1.0/A[i][1],1.0/A[i][2]};
sort(B,B+N);
rep(j,M+1)X[j]={0,j<1};
rep[B](a,N){
	X[M][0]+=X[M][1]*a[1];
	rrep(i,M){
		double p=X[i][1]*pow(1-a[3],M-i);
		X[M]={X[M][0]+p*a[1],X[M][1]+p};
		rrep(j,i+1,M){
			p=X[i][1]*pow(1-a[3],j-i)*a[3];
			X[j]={X[j][0]+p*a[2],X[j][1]+p};
		}
		X[i]={X[i][0]+X[i][1]*a[3]*a[2],X[i][1]*a[3]};
	}
}
wt(sum[double][i,0,M+1](X[i][0]));