The efficiency of primitive recursive functions: A programmer's view

If the conditional break and the decrement instructions are included in the Loop language, the ultimate obstinacy property does not hold. In this case, we use another approach for obtaining lower bounds. The unconditional break instruction does not avoid the obstinacy property; it is equivalent (in function and efficiency) to the conditional instruction if-then-else. The efficient implementation of other functions like step(x) (step(0)=0; step(x)=1 for x≥1) and min⁡(x,y) is also studied.