for s in[*open(0)][1:]:x,y,z=map(int,s.split());x+=y;print(-(x+z&1)or x+min(x,z)>>1)550B - Preparing Olympiad | 939B - Hamster Farm |
732A - Buy a Shovel | 1220C - Substring Game in the Lesson |
452A - Eevee | 1647B - Madoka and the Elegant Gift |
1408A - Circle Coloring | 766B - Mahmoud and a Triangle |
1618C - Paint the Array | 469A - I Wanna Be the Guy |
1294A - Collecting Coins | 1227A - Math Problem |
349A - Cinema Line | 47A - Triangular numbers |
1516B - AGAGA XOOORRR | 1515A - Phoenix and Gold |
1515B - Phoenix and Puzzle | 155A - I_love_username |
49A - Sleuth | 1541A - Pretty Permutations |
1632C - Strange Test | 673A - Bear and Game |
276A - Lunch Rush | 1205A - Almost Equal |
1020B - Badge | 1353A - Most Unstable Array |
770A - New Password | 1646B - Quality vs Quantity |
80A - Panoramix's Prediction | 1354B - Ternary String |