------
## 最终结论
Here's the complete Python code to solve the problem:

```python
def max_army_strength(t, test_cases):
    results = []
    for case in test_cases:
        n, q, strengths = case
        max_strength = 0
        current_strength = 0
        add_next = True
        
        for strength in strengths:
            if add_next:
                current_strength += strength
            else:
                current_strength -= strength
            add_next = not add_next

            max_strength = max(max_strength, current_strength)

        results.append(max_strength)
    
    return results

# Reading input and processing each test case
import sys

input_data = sys.stdin.read().strip().split()
index = 0

t = int(input_data[index])
index += 1

test_cases = []

for _ in range(t):
    n, q = map(int, input_data[index:index+2])
    index += 2
    strengths = list(map(int, input_data[index:index+n]))
    index += n
    test_cases.append((n, q, strengths))

results = max_army_strength(t, test_cases)

for result in results:
    print(result)
```

This code defines a function `max_army_strength` that calculates the maximal strength of the army for each test case. It reads input data from standard input, processes each test case to compute the maximal alternating sum of selected subsequences of Pokémon strengths, and prints the result for each test case.