Resistor color code decoder (4 & 5 band)

The idea in 30 seconds

• The first bands are digits: black 0, brown 1, red 2, orange 3, yellow 4, green 5, blue 6, violet 7, grey 8, white 9.
• The next band is the multiplier: how many zeros to add (gold = × 0.1, silver = × 0.01).
• The last band is the tolerance: gold ±5 %, silver ±10 %, brown ±1 %, red ±2 %.
• Example: brown-black-red-gold = 1, 0, × 100 = 1,000 Ω = 1 kΩ, ±5 %.