Author Archives: dmitriano

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29
06
21
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We’ll never get our Sparks

Posted by | Cryptocurrencies |

Below I provided my dialog with Binance support:

what about sparks?
I mean should I expect them?

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Can I know is this previous question or something else please ?

no, it is about Spark airdrop
I held XRP on December 2020

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Kindly wait please, we will check and get back to you as soon as possible.

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Upon checking, this airdrop of Spark tokens has not been sent yet, please follow our official announcements about this airdrop,
once we will distribute it, we will post official announcement here https://www.binance.com/en/support/announcement

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Is there anything else I can assist you?

is there some planned date when we'll get some Sparks?

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For now have to wait for the announcement since we don't have any planned date.

ok, thanks
(more…)
19
06
21
 1 Comment

Built my QT app for Android with API level 30 (Android 11)

Posted by | Android, QT |

New Android App Bundle and target API level requirements in 2021:

Starting August 2021, new apps will be required to target API level 30 (Android 11) and use the Android App Bundle publishing format. Starting November 2021, all app updates will be required to target API level 30 (Android 11). Apps with a download size of more than 150 MB are now supported by Play Asset Delivery and Play Feature Delivery.

I updated the manifest manually as follows:

<?xml version="1.0"?>
<manifest package="net.geographx.LinesGame" xmlns:android="http://schemas.android.com/apk/res/android" android:versionName="2.5.30" android:versionCode="161" android:installLocation="auto">
    <uses-sdk android:minSdkVersion="21" android:targetSdkVersion="30"/>
(more…)
17
06
21
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C++ tasks from Yandex

Posted by | C++ |

Task 1

At an interview I was asked how to by a given vector of integers build resulting vector containing the products of all the elements except current. Below I provided my solution in C++:

#include <vector>
#include <iostream>

using V = std::vector<int>;

V func(const V& v)
{
    V result;
    result.resize(v.size());

    int product = 1;

    for (size_t pos = 0; pos != v.size(); ++pos)
    {
        result[pos] = product;

        int a = v[pos];
        product *= a;
    }
(more…)
09
06
21
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Bought a terribly annoying video recorder from ZOSI

Posted by | Hardware |

Its Windows client simply crashes with the following message:

My device model number is ZR08WN HDD:2TB and the device QR code ends with 111A:

(more…)
08
06
21
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I transferred my domains to another registration service provider

Posted by | Uncategorized |

My Russian registration service provider has stopped working, but PublicDomainRegistry.com sent me the codes and I was able to transfer my domains to some ResellerClub prvider:

(more…)
05
06
21
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Range-based for loop with universal reference.

Posted by | C++ |

It is possible to iterate over std::vector with &&:

#include <vector>

class A {};

int main()
{
    std::vector<A> vec;
    for (auto&& v : vec)
    {
        static_cast<void>(v);
    }

    return 0;
}

Links:

05
06
21
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An annoying question about auto in C++

Posted by | C++ |

I was recently asked during a C++ job interview what are the types of riN variables in the code below:

int val = 25;

int foo() { return val; }
int& foo1() { return val; }
//warning: type qualifiers ignored on function return type
/*const*/ int foo2() { return val; }
const int& foo3() { return val; }

int main()
{
  auto ri = foo(); 
  auto ri1 = foo1();
  auto ri2 = foo2();
  auto ri3 = foo3();

  //cannot bind non-const lvalue reference of type 'int&' to an rvalue of type 'int'
  //auto& ri4 = foo();
  auto& ri5 = foo1();
  //cannot bind non-const lvalue reference of type 'int&' to an rvalue of type 'int'
  //auto& ri6 = foo2();
  auto& ri7 = foo3();

  auto&& ri8 = foo();
  auto&& ri9 = foo1();
  auto&& ri10 = foo2();
  auto&& ri11 = foo3();
    
  return 0;
}

auto ignores the type qualifiers and references, so looks like the types are simply int, int& and int&&.

22
05
21
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My QT Android app periodically crashes at android::RefBase::incStrong(void const*)

Posted by | Android, QT |

The call stack is:

  #00  pc 00000000000097a8  /system/lib/libutils.so (android::RefBase::incStrong(void const*) const+4)
  #00  pc 0000000000022145  /vendor/lib/libIMGegl.so
  #00  pc 000000000000ab79  /vendor/lib/libIMGegl.so (KEGLGetDrawableParameters+252)
  #00  pc 0000000000041c53  /vendor/lib/egl/libGLESv2_mtk.so
  #00  pc 000000000001663d  /vendor/lib/egl/libGLESv2_mtk.so
  #00  pc 0000000000016b01  /vendor/lib/egl/libGLESv2_mtk.so (glClear+440)
  #00  pc 000000000008acaf  /data/app/net.geographx.LinesGame-9_pUex92-tGEqE4iIbRCCw==/lib/arm/libLinesGameQt_armeabi-v7a.so (LinesGame::Squircle::beforeRendering()+270)
  #00  pc 000000000017d5b9  /data/app/net.geographx.LinesGame-9_pUex92-tGEqE4iIbRCCw==/lib/arm/libQt5Core_armeabi-v7a.so
  #00  pc 0000000000176f4d  /data/app/net.geographx.LinesGame-9_pUex92-tGEqE4iIbRCCw==/lib/arm/libQt5Quick_armeabi-v7a.so (QQuickWindowPrivate::renderSceneGraph(QSize const&, QSize const&)+172)

It is a QT bug that is not fixed yet.

Also my app crashes at the destructor of std::thread and this also a QT bug that is not fixed yet.

16
05
21
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The performance of my SSD NVMe drives

Posted by | Hardware |

Below I proved the results of speed tests of my 500 GB SSD M.2 Kingston NV1 [SNVS/500G] and 500 GB SSD M.2 Seagate BarraCuda Q5 [ZP500CV3A001]:

------------------------------------------------------------------------------
CrystalDiskMark 8.0.1 x64 (UWP) (C) 2007-2021 hiyohiyo
                                  Crystal Dew World: https://crystalmark.info/
------------------------------------------------------------------------------
* MB/s = 1,000,000 bytes/s [SATA/600 = 600,000,000 bytes/s]
* KB = 1000 bytes, KiB = 1024 bytes

[Read]
  SEQ    1MiB (Q=  8, T= 1):  2546.163 MB/s [   2428.2 IOPS] <  3291.40 us>
  SEQ    1MiB (Q=  1, T= 1):     0.000 MB/s [      0.0 IOPS] <     0.00 us>
  RND    4KiB (Q= 32, T= 1):   449.897 MB/s [ 109838.1 IOPS] <   281.99 us>
  RND    4KiB (Q=  1, T= 1):     0.000 MB/s [      0.0 IOPS] <     0.00 us>

[Write]
  SEQ    1MiB (Q=  8, T= 1):  1970.445 MB/s [   1879.2 IOPS] <  4243.49 us>
  SEQ    1MiB (Q=  1, T= 1):     0.000 MB/s [      0.0 IOPS] <     0.00 us>
  RND    4KiB (Q= 32, T= 1):   310.284 MB/s [  75752.9 IOPS] <   417.44 us>
  RND    4KiB (Q=  1, T= 1):     0.000 MB/s [      0.0 IOPS] <     0.00 us>

Profile: Default
   Test: 1 GiB (x5) [D: 18% (85/466GiB)]
   Mode:
   Time: Measure 5 sec / Interval 5 sec 
   Date: 2021/05/16 13:23:57
     OS: Windows 10 Professional [10.0 Build 19041] (x64)
(more…)
14
05
21
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Applying a path that fixes a bug in QT 5.15.2

Posted by | QT |

There was a bug in QT 5.15.2 that results in app crash on Android 5.1 and a patch:

Submodule qtbase contains modified content
diff --git a/qtbase/src/corelib/plugin/qlibrary_unix.cpp b/qtbase/src/corelib/plugin/qlibrary_unix.cpp
index a5c72f81d9..5cd21b67a4 100644
--- a/qtbase/src/corelib/plugin/qlibrary_unix.cpp
+++ b/qtbase/src/corelib/plugin/qlibrary_unix.cpp
@@ -243,10 +243,10 @@ bool QLibraryPrivate::load_sys()
             }
             if (hnd) {
                 using JniOnLoadPtr = jint (*)(JavaVM *vm, void *reserved);
-                JniOnLoadPtr jniOnLoad = reinterpret_cast<JniOnLoadPtr>(dlsym(pHnd, "JNI_OnLoad"));
+                JniOnLoadPtr jniOnLoad = reinterpret_cast<JniOnLoadPtr>(dlsym(hnd, "JNI_OnLoad"));
                 if (jniOnLoad && jniOnLoad(QtAndroidPrivate::javaVM(), nullptr) == JNI_ERR) {
                     dlclose(hnd);
-                    pHnd = nullptr;
+                    hnd = nullptr;
                 }
             }
 #endif

Looks like it was simply a typo and pHnd was replaced with hnd.

QT 5.15.3 where the bug was fixed is commercial so I applied the patch by myself (thanks to danilabagroff from stackoverflow.com):

(more…)
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