diff --git a/lab21/lab21.sln b/lab21/lab21.sln
new file mode 100644
index 0000000..dc3d5c7
--- /dev/null
+++ b/lab21/lab21.sln
@@ -0,0 +1,31 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.11.35327.3
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "lab21", "lab21\lab21.vcxproj", "{1B7473D9-9601-49B4-8E8D-E79262EED126}"
+EndProject
+Global
+ GlobalSection(SolutionConfigurationPlatforms) = preSolution
+ Debug|x64 = Debug|x64
+ Debug|x86 = Debug|x86
+ Release|x64 = Release|x64
+ Release|x86 = Release|x86
+ EndGlobalSection
+ GlobalSection(ProjectConfigurationPlatforms) = postSolution
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Debug|x64.ActiveCfg = Debug|x64
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Debug|x64.Build.0 = Debug|x64
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Debug|x86.ActiveCfg = Debug|Win32
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Debug|x86.Build.0 = Debug|Win32
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Release|x64.ActiveCfg = Release|x64
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Release|x64.Build.0 = Release|x64
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Release|x86.ActiveCfg = Release|Win32
+ {1B7473D9-9601-49B4-8E8D-E79262EED126}.Release|x86.Build.0 = Release|Win32
+ EndGlobalSection
+ GlobalSection(SolutionProperties) = preSolution
+ HideSolutionNode = FALSE
+ EndGlobalSection
+ GlobalSection(ExtensibilityGlobals) = postSolution
+ SolutionGuid = {07C7E4EC-6283-4FE7-849A-06A95F6722CA}
+ EndGlobalSection
+EndGlobal
diff --git a/lab21/lab21/lab21.vcxproj b/lab21/lab21/lab21.vcxproj
new file mode 100644
index 0000000..f934965
--- /dev/null
+++ b/lab21/lab21/lab21.vcxproj
@@ -0,0 +1,135 @@
+
+
+
+
+ Debug
+ Win32
+
+
+ Release
+ Win32
+
+
+ Debug
+ x64
+
+
+ Release
+ x64
+
+
+
+ 17.0
+ Win32Proj
+ {1b7473d9-9601-49b4-8e8d-e79262eed126}
+ lab21
+ 10.0
+
+
+
+ Application
+ true
+ v143
+ Unicode
+
+
+ Application
+ false
+ v143
+ true
+ Unicode
+
+
+ Application
+ true
+ v143
+ Unicode
+
+
+ Application
+ false
+ v143
+ true
+ Unicode
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+ Level3
+ true
+ WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)
+ true
+
+
+ Console
+ true
+
+
+
+
+ Level3
+ true
+ true
+ true
+ WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)
+ true
+
+
+ Console
+ true
+ true
+ true
+
+
+
+
+ Level3
+ true
+ _DEBUG;_CONSOLE;%(PreprocessorDefinitions)
+ true
+
+
+ Console
+ true
+
+
+
+
+ Level3
+ true
+ true
+ true
+ NDEBUG;_CONSOLE;%(PreprocessorDefinitions)
+ true
+
+
+ Console
+ true
+ true
+ true
+
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/lab21/lab21/lab21.vcxproj.filters b/lab21/lab21/lab21.vcxproj.filters
new file mode 100644
index 0000000..669bc4e
--- /dev/null
+++ b/lab21/lab21/lab21.vcxproj.filters
@@ -0,0 +1,22 @@
+
+
+
+
+ {4FC737F1-C7A5-4376-A066-2A32D752A2FF}
+ cpp;c;cc;cxx;c++;cppm;ixx;def;odl;idl;hpj;bat;asm;asmx
+
+
+ {93995380-89BD-4b04-88EB-625FBE52EBFB}
+ h;hh;hpp;hxx;h++;hm;inl;inc;ipp;xsd
+
+
+ {67DA6AB6-F800-4c08-8B7A-83BB121AAD01}
+ rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav;mfcribbon-ms
+
+
+
+
+ Исходные файлы
+
+
+
\ No newline at end of file
diff --git a/lab21/lab21/main.c b/lab21/lab21/main.c
new file mode 100644
index 0000000..22adae8
--- /dev/null
+++ b/lab21/lab21/main.c
@@ -0,0 +1,159 @@
+#include
+#include
+#include
+#include
+
+void task1() {
+ printf("task1 : ");
+ char ch;
+ scanf_s(" %c", &ch, 1);
+ for (int i = ch; i <= ch + 19; i++) {
+ printf("'%c' (%#x)(%d)\n", i, i, i);
+ }
+ printf("\n\n");
+}
+
+void task2() {
+ printf("task2 : ");
+ char ch;
+ scanf_s(" %c", &ch, 1);
+ for (int i = ch; i >= ch - 29; i--) {
+ printf("'%c' (%#x)(%d)\n", i, i, i);
+ }
+ printf("\n\n");
+}
+
+void task3() {
+ char str[81];
+ printf("task3 : ");
+ fgets(str, 81, stdin);
+ printf(" : \"%s\"\n", str);
+
+ int count = 0;
+ for (int i = 0; i < strlen(str); i++) {
+ if (str[i] == ' ') count++;
+ }
+ printf(" %d ", count);
+}
+
+void task4() {
+ char str[81];
+ printf("task4 : ");
+ fgets(str, 81, stdin);
+ printf(" : \"%s\"\n", str);
+
+ int count = 0;
+ for (int i = 0; i < strlen(str); i++) {
+ if (str[i] == ' ') str[i] = '#';
+ }
+ printf(" : \"%s\"\n", str);
+}
+
+void task5_1() {
+ char str[81];
+ printf("task5_1 : ");
+ fgets(str, 81, stdin);
+ printf(" : \"%s\"\n", str);
+
+ int count = 0;
+ for (int i = 0; i < strlen(str); i++) {
+ if (isdigit(str[i])) str[i] = '$';
+ }
+ printf(" : \"%s\"\n", str);
+}
+
+char isdigitMY(char ch) {
+ if (ch >= '0' && ch <= '9') {
+ return 1;
+ }
+ else {
+ return 0;
+ }
+}
+
+void task5_2() {
+ char str[81];
+ printf("task5_2 : ");
+ fgets(str, 81, stdin);
+ printf(" : \"%s\"\n", str);
+
+ int count = 0;
+ for (int i = 0; i < strlen(str); i++) {
+ if (isdigitMY(str[i])) str[i] = '$';
+ }
+ printf(" : \"%s\"\n", str);
+}
+
+void task6_1() {
+ char str[81];
+ printf("task6_1 : ");
+ fgets(str, 81, stdin);
+ printf(" : \"%s\"\n", str);
+
+ for (int i = 0; i < strlen(str); i++) {
+ str[i] = toupper(str[i]);
+ }
+
+ printf(" : \"%s\"\n", str);
+}
+
+char toupperMY(char ch) {
+ if (ch >= 'a' && ch <= 'z') {
+ return 'A' + (ch - 'a');
+ }
+ if (ch >= '' && ch <= '') {
+ return '' + (ch - '');
+ }
+ if (ch == '') {
+ return '';
+ }
+ return ch;
+}
+
+void task6_2() {
+ char str[81];
+ printf("task6_2 : ");
+ fgets(str, 81, stdin);
+ printf(" : \"%s\"\n", str);
+
+ for (int i = 0; i < strlen(str); i++) {
+ str[i] = toupperMY(str[i]);
+ }
+
+ printf(" : \"%s\"\n", str);
+}
+
+void task9_9() {
+ char str[81];
+ printf("task9_9 : ");
+ fgets(str, 81, stdin);
+ printf(" : \"%s\"\n", str);
+
+ for (int i = 0; i < strlen(str); i++) {
+ if (
+ str[i] == '!' || str[i] == '?' || str[i] == '.' ||
+ str[i] == ',' || str[i] == ':' || str[i] == ';' ||
+ str[i] == '\"' || str[i] == '\''
+ ) { str[i] = '_'; }
+ }
+
+ printf(" : \"%s\"\n", str);
+}
+
+int main() {
+ SetConsoleCP(1251);
+ SetConsoleOutputCP(1251);
+ setlocale(LC_CTYPE, "");
+
+ //task1();
+ //task2();
+ //task3();
+ //task4();
+ //task5_1();
+ //task5_2();
+ //task6_1();
+ //task6_2();
+ //task9_9();
+
+ return 0;
+}
\ No newline at end of file