C++ Learning Notes 8

for loop statement:Code for the “Knock the Table” game:

#include <iostream>using namespace std;

int main(){int counter = 0;for (int i = 1; i <= 100; i++)	{int ge = i % 10;int shi = i / 10 % 10;
if (ge == 7 || shi == 7 || i % 7 == 0)		{cout << "Knock the Table" << endl;counter++;		}else		{cout << i << endl;}
//cout << i << endl;
}cout << "Knock the Table appeared a total of " << counter << " times" << endl;

system("pause");return 0;}

Running result:Nested loops:Function: To nest another loop within the loop body to solve some practical problems.

#include <iostream>using namespace std;

int main(){for (int i = 0; i < 10; i++)	{for (int j = 0; j < 10; j++)		{cout << "* ";}
	cout << "\n";}
system("pause");return 0;}

Running result:Multiplication Table:

#include <iostream>using namespace std;

int main(){for (int i = 1; i < 10; i++)	{for (int j = 1; j <= i; j++)		{cout << j << "*" << i << "=" << i * j << "\t";}
	cout << endl;}
system("pause");return 0;}

Running result:Jump statements:break statement:Function: Used to exit a selection structure or loop structure.When to use break:1) Appears in a switch statement, its function is to terminate the case and exit the switch.2) Appears in a loop statement, its function is to exit the current loop statement.3) Appears in a nested loop, exits the nearest inner loop statement.

#include <iostream>using namespace std;
int main(){// When to use break
	cout << "Please select the difficulty level" << endl;
	cout << "1. Easy" << endl;
	cout << "2. Medium" << endl;
	cout << "3. Hard" << endl;
int select = 0;
	cin >> select;
switch (select)	{case 1:		cout << "Easy" << endl;break;case 2:		cout << "Medium" << endl;break;case 3:		cout << "Hard" << endl;break;default:		cout << "Input error" << endl;break;}
	system("pause");return 0;}

Running result:continue statement:Function: In a loop statement, skip the current loop and continue executing the next loop.

#include <iostream>using namespace std;
int main(){
	for (int i = 0; i < 100; i++)	{
		if (i % 2 == 0)		{
			continue;
		}
		cout << i << endl;
	}
system("pause");	return 0;}

Running result:goto statement:Function: Can unconditionally jump to a statement.Syntax: goto label;Explanation: If the label name already exists, executing the goto statement will jump to the label position.

#include <iostream>using namespace std;

int main(){
	cout << 1 << endl;
	goto FLAG;
	cout << 2 << endl;
	cout << 3 << endl;
	cout << 4 << endl;
FLAG:
	cout << 5 << endl;
	system("pause");	return 0;}

Running result: