never {
accept_init:
s0_init:
    if
    :: !(Q) -> goto s0_init
    :: (R) -> goto s0_init
    :: !(P) && (Q) && !(R) -> goto s2
    :: (Q) && !(R) -> goto accept_s1
    fi;
s2:
    if
    :: !(P) && !(R) -> goto s2
    :: (R) -> goto s0_init
    fi;
accept_s1:
    if
    :: !(R) -> goto accept_s1
    fi;
}