Decompiling the class file:

```java
import java.util.Arrays;

//
// Decompiled by Procyon v0.5.36
//

public class EZrev
{
public static void main(final String[] array) {
if (array.length != 1) {
System.out.println("L");
return;
}
final String s = array[0];
if (s.length() != 31) {
System.out.println("L");
return;
}
final int[] array2 = s.chars().toArray();
for (int i = 0; i < array2.length; ++i) {
if (i % 2 == 0) {
array2[i] = (char)(array2[i] ^ 0x13);
}
else {
array2[i] = (char)(array2[i] ^ 0x37);
}
}
for (int j = 0; j < array2.length / 2; ++j) {
if (j % 2 == 0) {
final int n = array2[j] - 10;
array2[j] = (char)(array2[array2.length - 1 - j] + 20);
array2[array2.length - 1 - j] = (char)n;
}
else {
array2[j] = (char)(array2[j] + 30);
}
}
if (Arrays.equals(array2, new int[] { 130, 37, 70, 115, 64, 106, 143, 34, 54, 134, 96, 98, 125, 98, 138, 104, 25, 3, 66, 78, 24, 69, 91, 80, 87, 67, 95, 8, 25, 22, 115 })) {
System.out.println("W");
}
else {
System.out.println("L");
}
}
}
```

Reverse the process using the script to get the flag (credits to my [teammate](https://github.com/hollowcrust))

```py
a = [130, 37, 70, 115, 64, 106, 143, 34, 54, 134, 96, 98, 125, 98, 138,
104, 25, 3, 66, 78, 24, 69, 91, 80, 87, 67, 95, 8, 25, 22, 115]

s = []

for i in range(15):
if(i%2!=0):
a[i] -= 30
else:
a[i], a[30-i] = a[30-i]+10, a[i]-20
for i in range(31):
if(i%2 == 0):
a[i] ^= 0x13
else:
a[i] ^= 0x37
for i in range(31):
print(chr(a[i]), end="")
```

Flag: `n00bz{r3v_1s_s0_e4zy_r1ght??!!}`