I am having a problem with something. i nead to assing values to parameters from input.dat file without using fscanf.

i need to use the terminal like a.out<input.dat>output.out

i have a file like this
GEN
0.0 2.1351 0.00001 500 o
PEND
0.12 0.1 0.15 0.5 0
0.16 0.11 0.8 -0.5 0
0.78 0.24 0.11 -0.5 0
SP
0.2 0.1

it is a mixture of strings and doubles, and each value here belongs to a different variable, how can i assing it from the file.

i know its basic but i need help