I've compiled the native activity sample and it runs fine. When I switch from main.c to main.cpp I get a compiler error 

$ /cygdrive/c/android-ndk-r7/ndk-build
make: *** No rule to make target `jni/main.c', needed by `obj/local/armeabi/objs/native-activity/main.o'.  Stop.


I changed the make file to main.cpp.

I'm new to Android and Linux. I'm using Cygwin. 


Question: What is the current flowing through this switch?
Answer: If you turn S1 on and wait long enough, the currents will eventually decay to zero (assuming non-ideal components). In the meantime,
the S1 current is equal to the sum of the two inductor currents. Redrawing the circuit like you did removes S1 altogether, which is okay unless you want to know the switch current. :-)

This circuit looks like a fancy switching regulator, so probably you wouldn't wait a long time. You would switch frequently, and vary the duty cycle to control the output voltage. It's easiest to understand if you look at it over two cycles:

1a. S2 on, V1 boosts the current in L1.

1b. S1 on, L1 pulls current through S1 and C1, charging up C2 (positive end away from V1).

2a. S2 on, C1 discharges through L2, boosting its current and feeding the load.

2b. S1 on, L2 pulls current through S1, feeding the load.

C2 acts as a filtering capacitor to reduce voltage ripple at the load. You can see that when S1 is on (steps 1b and 2b), both inductors are pulling current from ground through S1.