never {
accept_init:
s2_init:
    if
    :: (p) && (q) && (r) && (s) -> goto accept_s1
    :: !(p) -> goto s2_init
    :: (p) && (q) && (r) && !(s) -> goto s3
    :: (p) && !(q) -> goto accept_s4
    fi;
s3:
    if
    :: (q) && (r) && (s) -> goto accept_s1
    :: !(q) && !(s) -> goto s3
    :: (q) && (r) && !(s) -> goto s3
    :: !(q) && (s) -> goto accept_s4
    fi;
accept_s1:
    if
    :: !(q) && (s) -> goto accept_s4
    :: !(q) && !(s) -> goto s3
    :: (q) && (r) && !(s) -> goto s3
    :: (q) && (r) && (s) -> goto accept_s1
    fi;
accept_s4:
    if
    :: !(q) -> goto accept_s4
    :: (q) && (r) && !(s) -> goto s3
    :: (q) && (r) && (s) -> goto accept_s1
    fi;
}