Add the initial EN translation for C++ code (#1346)

en/codes/cpp/chapter_computational_complexity/iteration.cpp

@@ -0,0 +1,76 @@
+/**
+ * File: iteration.cpp
+ * Created Time: 2023-08-24
+ * Author: krahets (krahets@163.com)
+ */
+
+#include "../utils/common.hpp"
+
+/* for loop */
+int forLoop(int n) {
+    int res = 0;
+    // Loop sum 1, 2, ..., n-1, n
+    for (int i = 1; i <= n; ++i) {
+        res += i;
+    }
+    return res;
+}
+
+/* while loop */
+int whileLoop(int n) {
+    int res = 0;
+    int i = 1; // Initialize condition variable
+    // Loop sum 1, 2, ..., n-1, n
+    while (i <= n) {
+        res += i;
+        i++; // Update condition variable
+    }
+    return res;
+}
+
+/* while loop (two updates) */
+int whileLoopII(int n) {
+    int res = 0;
+    int i = 1; // Initialize condition variable
+    // Loop sum 1, 4, 10, ...
+    while (i <= n) {
+        res += i;
+        // Update condition variable
+        i++;
+        i *= 2;
+    }
+    return res;
+}
+
+/* Double for loop */
+string nestedForLoop(int n) {
+    ostringstream res;
+    // Loop i = 1, 2, ..., n-1, n
+    for (int i = 1; i <= n; ++i) {
+        // Loop j = 1, 2, ..., n-1, n
+        for (int j = 1; j <= n; ++j) {
+            res << "(" << i << ", " << j << "), ";
+        }
+    }
+    return res.str();
+}
+
+/* Driver Code */
+int main() {
+    int n = 5;
+    int res;
+
+    res = forLoop(n);
+    cout << "\nSum result of the for loop res = " << res << endl;
+
+    res = whileLoop(n);
+    cout << "\nSum result of the while loop res = " << res << endl;
+
+    res = whileLoopII(n);
+    cout << "\nSum result of the while loop (with two updates) res = " << res << endl;
+
+    string resStr = nestedForLoop(n);
+    cout << "\nResult of the double for loop traversal = " << resStr << endl;
+
+    return 0;
+}