﻿ Java exercises: Compute the sum of the prime numbers till 100 - w3resource # Java Exercises: Compute the sum of the prime numbers till 100

## Java Basic: Exercise-66 with Solution

Write a Java program to Compute the sum of the prime numbers till 100.

Pictorial Presentation: Sample Solution:

Java Code:

``````import java.util.*;
public class Exercise66 {
public static void main(String[] args)
{
int sum = 1;
int ctr = 0;
int n = 0;

while (ctr < 100) {
n++;
if (n % 2 != 0) {
// check if the number is even
if (is_Prime(n)) {
sum += n;
}
}
ctr++;
}
System.out.println("\nSum of the prime numbers till 100: "+sum);
}

public static boolean is_Prime(int n) {
for (int i = 3; i * i <= n; i+= 2) {
if (n % i == 0) {
return false;
}
}
return true;
}
}
```
```

Sample Output:

```Sum of the prime numbers till 100: 1060
```

Flowchart: Java Code Editor:

What is the difficulty level of this exercise?

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## Java: Tips of the Day

Execution of console commands:

Java allows you to execute console commands directly from code using a class Runtime. It is very important not to forget about exception handling.

For example, let's try to open a PDF file through a Java terminal:

```import java.io.BufferedReader;
import java.io.InputStream;

public class ShellCommandExec {

public static void main(String[] args) {
String gnomeOpenCommand = "gnome-open //home//user//Documents//MyDoc.pdf";

try {
Runtime rt = Runtime.getRuntime();
Process processObj = rt.exec(gnomeOpenCommand);

InputStream stdin = processObj.getErrorStream();

String myoutput = "";