Update do-while-loop.md (#196)

docs/day-05/do-while-loop.md

@@ -6,15 +6,119 @@ sidebar_label: "While and Do-While Loop"
 slug: while-and-do-while-loop-in-cpp
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-TASK:
-
-1. C++ while and do...while Loop
-2. C++ while Loop
-3. Flowchart of while Loop
-4. Example 1: Display Numbers from 1 to 5
-5. C++ do...while Loop
-6. Flowchart of do...while Loop
-7. Example 2: Display Numbers from 1 to 5
-
 IMAGE FILE:
 ![Do While Loop](../../static/img/day-05/while-do-while-loop-in-cpp.png)
+
+# 1. C++ while and do...while Loop
+
+In C++, `while` and `do-while loops` are control flow constructs used for repetitive execution of a block of code.
+
+In a `while` loop, the condition is checked before the loop body executes. In contrast, in a do-while loop, the condition is checked after the loop body executes.
+
+A `do-while` loop guarantees that the loop body is executed at least once, while a while loop may not execute at all if the initial condition is false.
+
+
+# 2. C++ while Loop
+
+The `while` loop repeatedly executes a target statement as long as a given condition is true. Its syntax is as follows:
+```cpp
+while (condition) {
+    // statement(s) to be executed as long as the condition is true
+}
+```
+
+# 3. Flowchart of while Loop
+
+```mermaid
+graph TD;
+    StartLoop --> ConditionEvaluation;
+    ConditionEvaluation --> |True| ConditionTrue;
+    ConditionEvaluation --> |False| EndLoop;
+    ConditionTrue --> ExecuteLoopBody;
+    ExecuteLoopBody --> UpdateLoopVariables;
+    UpdateLoopVariables --> ConditionEvaluation;
+    ConditionTrue --> ConditionEvaluation;
+```
+
+
+**Explanation:**
+
+- The loop begins with the "StartLoop" block.
+- The condition is evaluated at the "ConditionEvaluation" block. If the condition is false, the loop terminates, and control passes to the "EndLoop" block.
+- If the condition is true, the loop body is executed, as indicated by the "ExecuteLoopBody" block.
+- After executing the loop body, any necessary variable updates are performed (e.g., incrementing a counter).
+- Control then returns to the "ConditionEvaluation" block, where the condition is checked again.
+- This process continues until the condition becomes false, at which point the loop terminates, and control passes to the "EndLoop" block.
+
+This flowchart represents the basic structure of a `while` loop and illustrates how the loop iterates as long as the condition remains true.
+
+# 4. Example 1: Display Numbers from 1 to 5
+
+```cpp
+#include <iostream>
+
+int main() {
+    int num = 1;
+
+    while (num <= 5) {
+        std::cout << num << " ";
+        num++;
+    }
+
+    return 0;
+}
+```
+
+# 5. C++ do...while Loop
+
+The `do-while` loop is similar to the while loop, but with one crucial difference: the condition is evaluated after the loop body executes, ensuring that the loop body is executed at least once. Its syntax is as follows:
+
+```cpp
+do {
+    // statement(s) to be executed
+} while (condition);
+```
+
+
+# 6. Flowchart of do...while Loop
+
+```mermaid
+graph TD;
+    StartLoop --> ExecuteLoopBody;
+    ExecuteLoopBody --> UpdateLoopVariables;
+    UpdateLoopVariables --> ConditionEvaluation;
+    ConditionEvaluation --> |True| ConditionTrue;
+    ConditionEvaluation --> |False| EndLoop;
+    ConditionTrue --> ExecuteLoopBody;
+```
+
+
+**Explanation:**
+
+- The loop begins with the "StartLoop" block.
+- The loop body is executed first at the "ExecuteLoopBody" block.
+- After executing the loop body, any necessary variable updates are performed (e.g., incrementing a counter) at the "UpdateLoopVariables" block.
+- Control then proceeds to the "ConditionEvaluation" block, where the condition is checked.
+- If the condition is true, control returns to the "ExecuteLoopBody" block, and the loop body is executed again.
+- This process continues until the condition becomes false, at which point the loop terminates, and control passes to the "EndLoop" block.
+
+This flowchart represents the structure of a `do-while` loop, where the loop body is executed at least once before checking the loop condition.
+
+
+# 7. Example 2: Display Numbers from 1 to 5
+
+```cpp
+#include <iostream>
+
+int main() {
+    int num = 1;
+
+    do {
+        std::cout << num << " ";
+        num++;
+    } while (num <= 5);
+
+    return 0;
+}
+```
+