Update readme.md

Author: garyexplains

rp2350/readme.md

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 Source code to accompany my video: Raspberry Pi RP2350 vs RP2040 - Performance and Power, including Arm Cortex-M33 vs Hazard RISC-V (https://youtu.be/RrE3bw_HYIU)
 
 This video explores the performance of the Cortex-M0+ in the Raspberry Pi RP2040, the Cortex-M33 in the new RP2350, and the Hazard3 RISC-V in the RP2350. It includes four different benchmarks along with power consumption data!
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+The bulk of the code for the nqueens problem is from https://rosettagit.org/drafts/n-queens-problem/#c