speak in details what happens fromswitching on the computer to loading the operating system interface on the screen

Cprogram to find //perimeter of rectangle printf(" \n perimeter of rectangle \n"); printf(""); printf("\n enter width and length of the rectangle : "); scanf("%f%f", & width,& length); perimeter = 2 * (width + length); printf("perimeter of rectangle is: %.3f", perimeter);  

"computer screen desktop"? what? that phrase makes no sense, and it has nothing to do with modifying system components i assure you.

You would get