all lights on William's gadget are wound down. Toward the start of another emphasis the gadget arbitrarily, with a uniform dissemination, picks a light that is wound down and turns it on, let William know which digital money he ought to put resources into. After this cycle on the off chance that any k back to back lights contain more than one turned
At first, all lights on William's gadget are wound down. Toward the start of another emphasis the gadget arbitrarily, with a uniform dissemination, picks a light that is wound down and turns it on, let William know which digital money he ought to put resources into. After this cycle on the off chance that any k back to back lights contain more than one turned on light, the gadget gets done with working.
William doesn't care for vulnerability, so he needs you to ascertain the normal worth of the number of lights that are turned on in the gadget after it gets done with working.
Input
Each test contains various experiments. The primary line contains the number of experiments t (1≤t≤10). Depiction of the experiments follows.
The main line for each experiment contains two integers n and k (2≤k≤n≤105), which are the complete number of lights and the length of subsegment of lights that are being checked, separately.
Output
For each experiment print the appropriate response, modulo 109+7.
Officially, let M=109+7. It tends to be shown that the appropriate response can be communicated as a final portion pq, where p and q are integers and q≢0(modM). Output the integer equivalent to p⋅q−1modM. All in all, output such an integer x that 0≤x<M and x⋅q≡p(modM).
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