– 4 + 5 – 6 +7 – 8 + 9 – 10 +11 – 25 – 26 – 27 – 28 – 29 + 28+ 27 +26 – 19 – 18 –1 7 – 16 – … – 1+ 0 +1 + …+ 16+ 17 + 18 + 19 +20 – 7 + 8 – 9 +10 – 11 + 12 – 13 +14 – 21 – 22 – 23 – 24 – 25 + 24+ 23 +22 – 14 – 13 –1 2 – 11 – … ...

– 4 + 5 – 6 +7 – 8 + 9 – 10 +11 – 25 – 26 – 27 – 28 – 29 + 28+ 27 +26 – 19 – 18 –1 7 – 16 – … – 1+ 0 +1 + …+ 16+ 17 + 18 + 19 +20 – 7 + 8 – 9 +10 – 11 + 12 – 13 +14 – 21 – 22 – 23 – 24 – 25 + 24+ 23 +22 – 14 – 13 –1 2 – 11 – … – 1+ 0 +1 + …+ 11+ 12 + 13 + 14 +15 Помогите решить удобным способом.