<font size="4" style="font-family: Arial; color: rgb(0, 166, 80);">a) 1.c6-c7! zugzwang. <br /> <br />    1...Kc5-c6 <br /> <br />    2. c7-c8=S zugzwang. <br /> <br />    2...Kc6-c5 <br /> <br />    3. Ra7-c7 # <br /> <br />    1...Kc5-b6 <br /> <br />    2. c7-c8=Q threat: <br /> <br />    3. Qc8-c7 # <br /> <br />    3. Ra7-a6 # <br /> <br />    3. Bc3-d4 # <br /> <br />    2...Kb6*a7 <br /> <br />    3. Bc3-d4 # <br /> <br />    1...Kc5-d6 <br /> <br />    2. c7-c8=R zugzwang. <br /> <br />    2...Kd6-e6 <br /> <br />    3. Rc8-c6 # <br /> <br />   <br /> <br />   <br /> <br /> <span style="font-weight: bold;">b) Ra7 - e7</span> <br /> <br />   1. c6-c7! zugzwang. <br /> <br /> 1...Kc5-b6 <br /> <br /> 2. c7-c8=R zugzwang. <br /> <br /> 2...Kb6-a6 <br /> <br /> 3. Rc8-c6 # <br /> <br /> 1...Kc5-c6 <br /> <br /> 2.c7-c8=S zugzwang. <br /> <br /> 2...Kc6-c5 <br /> <br /> 3. Re7-c7 # <br /> <br /> 1...Kc5-d6 <br /> <br /> 2. c7-c8=Q threat: <br /> <br /> 3. Qc8-c7 # <br /> <br /> 3. Re7-e6 # <br /> <br /> 3. Bc3-b4 # <br /> <br /> 2...Kd6*e7 <br /> <br /> 3. Bc3-b4 # <br /> <br />   <br /> <br /> Чередование превращений по циклу ABC – BCA.  <span style="color: rgb(255, 0, 0);"> Author</span> <br /> <br /> </font>