1. Run S3.
2. Connect it to S4 and S5. Check if PreviousTaskStatusS3 = 
succeeded in the connecting link.
3. Once S3 is successfully executed it will start S4 and S5
4. Use a decision task and input that from S4 and S5. In 
the decision use  
PreviousTaskStatusS4 = succeeded or PreviousTaskStatusS5 = 
succeeded
5. This will allow you to move ahead incase either of S4 or 
S5 is succeeded.
6.Connect it to S1 using the same PreviousTaskStatus = 
succeeded.
7.Connect it to S2 using the same PreviousTaskStatus = 
succeeded.

This way the required job will be done.