Embedded systems course

Write a C code about traffic signal with 2 modes, daylight mode, and night mode. you required to design the traffic signal in the following cases, in daylight mode, signal should operate 40 sec. each stage, red, yellow, and green. You have 7 segment display, you should display, how many remaining seconds, until the signal close or open. The night mode same as the daylight mode, but the time increased to double i.e 80 sec. When night came, the signal should convert automatically to the night mode. Requirements: give you list of components and you to choose which components will you use, transistors, light sensor, leds, temp. sensor, 7 segment display .. etc. After you choose the components, u should draw the circuit using the mbed, and put the connections from/to mbed. Please help me and need the code in C code not C++ code Thanks