// QFT and measure, version 1
OPENQASM 2.0;
include "qelib1.inc";
qreg q[4];
creg c[4];
h q;
barrier q;
h q[0];
measure q[0] -> c[0];
if(c==1) u1(pi/2) q[1];
h q[1];
measure q[1] -> c[1];
if(c==1) u1(pi/4) q[2];
if(c==2) u1(pi/2) q[2];
if(c==3) u1(pi/2+pi/4) q[2];
h q[2];
measure q[2] -> c[2];
if(c==1) u1(pi/8) q[3];
if(c==2) u1(pi/4) q[3];
if(c==3) u1(pi/4+pi/8) q[3];
if(c==4) u1(pi/2) q[3];
if(c==5) u1(pi/2+pi/8) q[3];
if(c==6) u1(pi/2+pi/4) q[3];
if(c==7) u1(pi/2+pi/4+pi/8) q[3];
h q[3];
measure q[3] -> c[3];