/** * 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; }