add first lesson

maatriks/.vscode/launch.json

+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "gcc - Build and debug active file",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${fileDirname}/${fileBasenameNoExtension}",
+            "args": [],
+            "stopAtEntry": false,
+            "cwd": "${workspaceFolder}",
+            "environment": [],
+            "externalConsole": false,
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ],
+            "preLaunchTask": "C/C++: gcc build active file",
+            "miDebuggerPath": "/usr/bin/gdb"
+        }
+    ]
+}
\ No newline at end of file

maatriks/diagram.uxf

+<diagram program="umletino" version="14.4.0-SNAPSHOT"><zoom_level>10</zoom_level><element><id>UMLClass</id><coordinates><x>310</x><y>170</y><w>100</w><h>30</h></coordinates><panel_attributes>SimpleClass</panel_attributes><additional_attributes></additional_attributes></element></diagram>
\ No newline at end of file

maatriks/maatriks.c

+#include <stdio.h>
+
+//Leiame peadiagonaali elementide summa
+
+int main(void)
+{
+    int N, i, j, S = 0;
+
+    do
+    {
+        printf("Sisestage ruutmatriksi mõõde N\n");
+        scanf("%d", &N);
+    } while (N <= 0);
+
+    int A[N][N];
+
+    // Sisestus blokk
+    for (i = 0; i < N; i++)
+    {
+        for (j = 0; j < N; j++)
+        {
+            printf("Sisestage arv kohal A[%d][%d]\n", i, j);
+            scanf("%d", &A[i][j]);
+        }
+    }
+
+    // //Tootlus blokk
+    for (i = 0; i < N; i++)
+    {
+        for (j = 0; j < N; j++)
+        {
+            if (A[i][j] > 0) //On Leitud vähemalt üks liige
+            {
+
+                if (S == 0) { // 0-iga ei saa korrutada
+                    S = 1;
+                }
+                S = S * A[i][j];
+            }
+        }
+    }
+
+    printf("Vastus int:%d\n", S);
+
+    return 0;
+}
\ No newline at end of file