Just read Rust Brain Teasers and I needed a place to play with the code. Also using this workspace to try the brain teasers in other languages.
Three and a Bit
$ cargo run --bin three_and_a_bit
Finished dev [unoptimized + debuginfo] target(s) in 0.01s
Running `target/debug/three_and_a_bit three_and_a_bit`
Wanted: 3.4028236
Got: 3.4028237
Non-Standard Input
$ cargo run --bin non-std-input
Finished dev [unoptimized + debuginfo] target(s) in 0.00s
Running `target/debug/non-std-input`
Type your answer and press enter.
What is 3+2?
5
Response: "5\n"
Trimmed: "5"
Correct!
$ cargo run --bin non-std-input
Finished dev [unoptimized + debuginfo] target(s) in 0.00s
Running `target/debug/non-std-input`
Type your answer and press enter.
What is 3+2?
7
Response: "7\n"
Trimmed: "7"
Incorrect!
Type Conversion
$ cargo run --bin type-conversion
Finished dev [unoptimized + debuginfo] target(s) in 0.01s
Running `target/debug/type-conversion`
x1(4294967296) doesn't equal y1(0)
x2(4294967296) equals y2(4294967296)
thread 'main' panicked at type-conversion/src/main.rs:21:33:
Failed to convert from u64 to u32: TryFromIntError(())
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
$ RUST_BACKTRACE=1 cargo run --bin type-conversion
Finished dev [unoptimized + debuginfo] target(s) in 0.01s
Running `target/debug/type-conversion`
x1(4294967296) doesn't equal y1(0)
x2(4294967296) equals y2(4294967296)
thread 'main' panicked at type-conversion/src/main.rs:21:33:
Failed to convert from u64 to u32: TryFromIntError(())
stack backtrace:
0: rust_begin_unwind
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:647:5
1: core::panicking::panic_fmt
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/panicking.rs:72:14
2: core::result::unwrap_failed
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/result.rs:1649:5
3: core::result::Result<T,E>::expect
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/result.rs:1030:23
4: type_conversion::main
at ./type-conversion/src/main.rs:21:19
5: core::ops::function::FnOnce::call_once
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/ops/function.rs:250:5
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
$ RUST_BACKTRACE=full cargo run --bin type-conversion
Finished dev [unoptimized + debuginfo] target(s) in 0.01s
Running `target/debug/type-conversion`
x1(4294967296) doesn't equal y1(0)
x2(4294967296) equals y2(4294967296)
thread 'main' panicked at type-conversion/src/main.rs:21:33:
Failed to convert from u64 to u32: TryFromIntError(())
stack backtrace:
0: 0x55c00e69a236 - std::backtrace_rs::backtrace::libunwind::trace::h6e4a662bea54ccfc
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
1: 0x55c00e69a236 - std::backtrace_rs::backtrace::trace_unsynchronized::hb42b4eb2797d9c0e
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
2: 0x55c00e69a236 - std::sys_common::backtrace::_print_fmt::h2bc261f3223f4e4d
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/sys_common/backtrace.rs:68:5
3: 0x55c00e69a236 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h9cca0343d66d16a8
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/sys_common/backtrace.rs:44:22
4: 0x55c00e6b8ee0 - core::fmt::rt::Argument::fmt::h8b666c45176be671
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/fmt/rt.rs:142:9
5: 0x55c00e6b8ee0 - core::fmt::write::h4311bce0ee536615
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/fmt/mod.rs:1120:17
6: 0x55c00e69841f - std::io::Write::write_fmt::h0685c51539d0a0cd
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/io/mod.rs:1846:15
7: 0x55c00e69a014 - std::sys_common::backtrace::_print::h25f19b1d64e81f86
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/sys_common/backtrace.rs:47:5
8: 0x55c00e69a014 - std::sys_common::backtrace::print::h2fb8f70628a241ed
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/sys_common/backtrace.rs:34:9
9: 0x55c00e69b577 - std::panicking::default_hook::{{closure}}::h05093fe2e3ef454d
10: 0x55c00e69b2d9 - std::panicking::default_hook::h5ac38aa38e0086d2
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:292:9
11: 0x55c00e69ba08 - std::panicking::rust_panic_with_hook::hed79743dc8b4b969
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:781:13
12: 0x55c00e69b8e2 - std::panicking::begin_panic_handler::{{closure}}::ha437b5d58f431abf
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:659:13
13: 0x55c00e69a736 - std::sys_common::backtrace::__rust_end_short_backtrace::hd98e82d5b39ec859
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/sys_common/backtrace.rs:171:18
14: 0x55c00e69b634 - rust_begin_unwind
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:647:5
15: 0x55c00e67e0e5 - core::panicking::panic_fmt::hc69c4d258fe11477
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/panicking.rs:72:14
16: 0x55c00e67e553 - core::result::unwrap_failed::hff299ec748d62aab
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/result.rs:1649:5
17: 0x55c00e67ed40 - core::result::Result<T,E>::expect::h0973832121af6a60
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/result.rs:1030:23
18: 0x55c00e67f176 - type_conversion::main::h986510cef192d252
at /home/vpayno/git_vpayno/brain-teasers-workspace/type-conversion/src/main.rs:21:19
19: 0x55c00e67ec4b - core::ops::function::FnOnce::call_once::h86b1730ea98a684d
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/ops/function.rs:250:5
20: 0x55c00e67ebce - std::sys_common::backtrace::__rust_begin_short_backtrace::hce82ff96ca4e6e30
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/sys_common/backtrace.rs:155:18
21: 0x55c00e67f3d1 - std::rt::lang_start::{{closure}}::h595a572b5b246a07
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/rt.rs:166:18
22: 0x55c00e695be1 - core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once::h8c00837184d6f522
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/core/src/ops/function.rs:284:13
23: 0x55c00e695be1 - std::panicking::try::do_call::hfd8273c3b0a89311
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:554:40
24: 0x55c00e695be1 - std::panicking::try::h389092b34a7cd1de
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:518:19
25: 0x55c00e695be1 - std::panic::catch_unwind::hd784b6d233abd2d5
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panic.rs:142:14
26: 0x55c00e695be1 - std::rt::lang_start_internal::{{closure}}::h8d693c96d9aec4f8
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/rt.rs:148:48
27: 0x55c00e695be1 - std::panicking::try::do_call::h62b442e92648318b
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:554:40
28: 0x55c00e695be1 - std::panicking::try::h3dd33ffb0232e2bf
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panicking.rs:518:19
29: 0x55c00e695be1 - std::panic::catch_unwind::h388a168fe640f06a
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/panic.rs:142:14
30: 0x55c00e695be1 - std::rt::lang_start_internal::hdaf8b62dc8f7de54
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/rt.rs:148:20
31: 0x55c00e67f3aa - std::rt::lang_start::h9334eecc88da7978
at /rustc/7cf61ebde7b22796c69757901dd346d0fe70bd97/library/std/src/rt.rs:165:17
32: 0x55c00e67f36e - main
33: 0x7f5feab9224a - __libc_start_call_main
at ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16
34: 0x7f5feab92305 - __libc_start_main_impl
at ./csu/../csu/libc-start.c:360:3
35: 0x55c00e67e811 - _start
36: 0x0 - <unknown>
Byte-Sized Chunks
$ cargo run --bin byte-sized-chunks
Compiling byte-sized-chunks v0.1.0 (/home/vpayno/git_vpayno/brain-teasers-workspace/byte-sized-chunks)
Finished dev [unoptimized + debuginfo] target(s) in 0.10s
Running `target/debug/byte-sized-chunks`
Properly handling arithmetic overflow using .checked_add() ...
1
9
17
25
33
41
49
57
65
73
81
89
97
105
113
121
Properly handling arithmetic overflow using Wrapping() ...
1
9
17
25
33
41
49
57
65
73
81
89
97
105
113
121
Improperly handling arithmetic overflow...
1
9
17
25
33
41
49
57
65
73
81
89
97
105
113
121
thread 'main' panicked at byte-sized-chunks/src/main.rs:24:9:
attempt to add with overflow
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
How long is a string?
$ cargo run --bin how-long-is-a-string
Finished dev [unoptimized + debuginfo] target(s) in 0.00s
Running `target/debug/how-long-is-a-string`
string | length | bytes | chars
------------------------------------------
Hello world! | 12 | 12 | 12
abc | 3 | 3 | 3
12345 | 5 | 5 | 5
｡◕‿◕｡ | 15 | 15 | 5
ᕙ༼◕ ᴥ ◕༽ᕗ | 23 | 23 | 9
Héllö Wórld! | 15 | 15 | 12
Please Reboot The Universe
$ cargo run --bin please-reboot-the-universe
Compiling please-reboot-the-universe v0.1.0 (/home/vpayno/git_vpayno/brain-teasers-workspace/please-reboot-the-universe)
Finished dev [unoptimized + debuginfo] target(s) in 0.12s
Running `target/debug/please-reboot-the-universe`
Does 0.1 + 0.2 == 0.3 ?
0.1 + 0.2 equals 0.30000000000000004
Please reboot the universe.
There and Back Again
$ cargo run --bin there-and-back-again
Finished dev [unoptimized + debuginfo] target(s) in 0.00s
Running `target/debug/there-and-back-again`
180 Degrees in Radians = 3.1415927
any number: 7
zero to ten? 7
any number: 42
thread 'main' panicked at there-and-back-again/src/main.rs:52:41:
called `Result::unwrap()` on an `Err` value: "Value must be between 0 and 10"
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Walks Like a Duck, Quacks Like a Duck
$ cargo run --bin walks-like-a-duck-quacks-like-a-duck
Compiling walks-like-a-duck-quacks-like-a-duck v0.1.0 (/home/vpayno/git_vpayno/brain-teasers-workspace/walks-like-a-duck-quacks-like-a-duck)
Finished dev [unoptimized + debuginfo] target(s) in 0.10s
Running `target/debug/walks-like-a-duck-quacks-like-a-duck`
one: 1, "i32"
double: 2, "u64"
triple: 3, "u128"
Out of Order
$ cargo run --bin out-of-order
Finished dev [unoptimized + debuginfo] target(s) in 0.01s
Running `target/debug/out-of-order`
unsorted floats: [
3.1,
1.2,
4.5,
0.3,
]
sorted floats: [
0.3,
1.2,
3.1,
4.5,
]
reversed floats: [
4.5,
3.1,
1.2,
0.3,
]
unsorted floats2: [
3.1,
1.2,
4.5,
0.3,
inf,
NaN,
]
sorted floats2: [
NaN,
0.3,
1.2,
3.1,
4.5,
inf,
]
X Marks the Spot
$ cargo run --bin x-marks-the-spot
Finished dev [unoptimized + debuginfo] target(s) in 0.01s
Running `target/debug/x-marks-the-spot`
X (bytes:[
88,
]) is not equal to Ｘ (bytes:[
239,
188,
184,
])
Stacking Boxes
$ cargo run --bin stacking-boxes
Compiling stacking-boxes v0.1.0 (/home/vpayno/git_vpayno/brain-teasers-workspace/stacking-boxes)
Finished dev [unoptimized + debuginfo] target(s) in 0.13s
Running `target/debug/stacking-boxes`
thread 'main' has overflowed its stack
fatal runtime error: stack overflow
$ cargo run --bin stacking-boxes --release
Compiling stacking-boxes v0.1.0 (/home/vpayno/git_vpayno/brain-teasers-workspace/stacking-boxes)
Finished release [optimized] target(s) in 0.10s
Running `target/release/stacking-boxes`
Box Length: 10000000
Amnesia
$ sudo cgcreate -g memory:rust_mem_cg
$ echo 100M | sudo tee /sys/fs/cgroup/memory/myGroup/memory.limit_in_bytes
100M
$ echo 200M | sudo tee /sys/fs/cgroup/memory/myGroup/memory.memsw.limit_in_bytes
200M
$ cargo build --bin amnesia
Compiling amnesia v0.1.0 (/home/vpayno/git_vpayno/brain-teasers-workspace/amnesia)
Finished dev [unoptimized + debuginfo] target(s) in 0.11s
$ sudo cgexec -g memory:rust_mem_cg target/debug/amnesia
Using std::mem::forget() to intentionally leak memory
counter: 0
counter: 1000
counter: 2000
counter: 3000
counter: 4000
counter: 5000
counter: 6000
counter: 7000
counter: 8000
counter: 9000
counter: 10000
counter: 11000
counter: 12000
counter: 13000
counter: 14000
counter: 15000
counter: 16000
counter: 17000
Killed