public class Main {
public static void main(String[] args) {
for (int i = 0; i < 4; i++) {
System.out.println(i);
} // end of for
}
}
0
1
2
3
?×× ×××פה ×××
public class Main {
public static void main(String[] args) {
int i = 10;
for ( ; i > 5; i--)
System.out.print(i + ", ");
}
}
10, 9, 8, 7, 6,
?×× ×××פה ×××
public class Main {
public static void main(String[] args) {
for (int i = 10; i < 20; i++) {
System.out.print(i + ", ");
i++;
} // end of for
}
}
10, 12, 14, 16, 18,
?×× ×××פה ×××
public class Main {
public static void main(String[] args) {
for (int i = 0; i < 10; i++) {
if (i==3)
continue;
else if (i==6)
break;
System.out.print(i + ", ");
} // end of for
}
}
0, 1, 2, 4, 5,
explanation
the keyword continue will continue to the next number in the loop
public class Main {
public static void main(String[] args) {
int n = 5; // or enter from user
int factorial = 1;
for (int i = 1; i <= n; i++)
factorial*=i;
System.out.println(n + "! = " + factorial);
int sum = 0;
for (int i = 1; i <= n; i++)
sum+=i;
System.out.println("Summation of " + n + " = " + sum);
}
}
public class Main {
public static void main(String[] args) {
int n;
while ((n = MyConsole.readInt("enter num: "))!=-1){
int factorial = 1;
for (int i = 1; i <= n; i++)
factorial*=i;
System.out.println(n + "! = " + factorial);
int sum = 0;
for (int i = 1; i <= n; i++)
sum+=i;
System.out.println("Summation of " + n + " = " + sum);
}
}
}
enter num: 5
5! = 120
Summation of 5 = 15
enter num: 10
10! = 3628800
Summation of 10 = 55
enter num: -1
Question - Formula āā
×Ŗק×××× ××Ŗ ×× ××”×× ×××:
(a+20ā b),(a+20ā b+21ā b),..,,(a+20ā b+21ā b+...+2nā1ā b)
public class Main {
public static void main(String[] args) {
int a = MyConsole.readInt("enter a: ");
int b = MyConsole.readInt("enter b: ");
int n = MyConsole.readInt("enter n: ");
int sum = a;
for (int i = 0; i < n; i++) {
sum+=Math.pow(2,i)*b;
System.out.println(sum);
}
}
}
public class Main{
public static void main(String[] args) {
int n = MyConsole.readInt("enter number: ");
int numerator = 1;
int denominator1 = 1;
int denominator2 = 1;
//numerator
for (int i = 1; i <= n * 2; i++)
numerator *= i;
//denominator
for (int i = 1; i <= n; i++)
denominator1 *= i;
denominator2 = denominator1*(n+1);
int result = numerator/(denominator1*denominator2);
System.out.println("C_"+ n + " = " + result);
}
}
public class Main{
public static void main(String[] args) {
int n = MyConsole.readInt("enter number: ");
for (int each_c = 0; each_c <= n; each_c++) {
int numerator = 1;
int denominator1 = 1;
int denominator2 = 1;
//numerator
for (int i = 1; i <= each_c * 2; i++)
numerator *= i;
//denominator
for (int i = 1; i <= each_c; i++)
denominator1 *= i;
denominator2 = denominator1*(each_c+1);
int result = numerator/(denominator1*denominator2);
System.out.println("C_"+ each_c + " = " + result);
}
}
}
public class Main{
public static void main(String[] args) {
for (int i = 1; i < 10; i++) {
for (int j = 1; j < 10; j++)
System.out.print(j + "x" + i +"=" +(i*j) +"\t");
System.out.println();
}
}
}
public class Main{
public static void main(String[] args) {
double e = 1;
double x = MyConsole.readDouble("enter exponent: ");
double accuracy = MyConsole.readDouble("enter accuracy: ");
for (int n = 1; n <= accuracy; n++) {
int factorial = 1;
//find factorial
for (int i = 1; i <= n; i++) {
factorial*=i;
} // end of inner for
e += Math.pow(x, n)/factorial;
} // end of outer for
System.out.println("e^"+ x +" = " + e);
}
}
enter exponent: 3
enter accuracy: 12
e^3.0 = 20.08521256087662
in the outer loop
for (int n = 1; n <= accuracy; n++) {
int factorial = 1;
each time we reset factorial to calculate the factorial
while the inner loop runs until n each time
for (int n = 1; n <= accuracy; n++) {
...
for (int i = 1; i <= n; i++) {
version 2
display each accuracy until n
public class Main{
public static void main(String[] args) {
double e = 1;
double x = MyConsole.readDouble("enter exponent: ");
double accuracy = MyConsole.readDouble("enter accuracy: ");
double real_value_of_e = 2.718281828459045;
for (int i = 1; i <= accuracy; i++) {
e = 1;
for (int n = 1; n <= i; n++) {
int factorial = 1;
//factorial
for (int j = 1; j <= n; j++) {
factorial*=j;
} // end of inner for
e += Math.pow(x, n)/factorial;
} // end of middle for
System.out.println("accuracy: "+ i + ", e^"+ (int)x +" = " + e + ", loss of: " + (real_value_of_e-e));
} // end of outer for
}
}
enter exponent: 1
enter accuracy: 10
accuracy: 1, e^1 = 2.0, loss of: 0.7182818284590451
accuracy: 2, e^1 = 2.5, loss of: 0.2182818284590451
accuracy: 3, e^1 = 2.6666666666666665, loss of: 0.05161516179237857
accuracy: 4, e^1 = 2.708333333333333, loss of: 0.009948495125712054
accuracy: 5, e^1 = 2.7166666666666663, loss of: 0.0016151617923787498
accuracy: 6, e^1 = 2.7180555555555554, loss of: 2.262729034896438E-4
accuracy: 7, e^1 = 2.7182539682539684, loss of: 2.7860205076724043E-5
accuracy: 8, e^1 = 2.71827876984127, loss of: 3.0586177750535626E-6
accuracy: 9, e^1 = 2.7182815255731922, loss of: 3.0288585284310443E-7
accuracy: 10, e^1 = 2.7182818011463845, loss of: 2.7312660577649694E-8
think how large 12! is its 479,001,600
Remember than e = 2.718281828459045 which isn't bad at all, each time we are accurate by one decimal