We like indentation here, but this is not Python, and indentation is no substitute for getting the braces right:
Code:for(i=0; i<min_in_trip/5; i++) { for(j=0; j<300; j++) { fscanf(ifp, "%f%f", &temp, &temp2); numrevs += temp; gas += temp2; } if(j == 300) array[i] = findfueleff(radius, numrevs, gas); }