conditional-statements

I have a file: P 0.5 0.6 0.3 30 300 80 150 160 400 200 150 250 300 T r 45 0 0 s 0.5 1.5 0 0 t 200 –150 . . . When I read in 'P' I know that 3 floats will follow. That will be followed by a finite number of X and Y coordinates. The number will vary until a 'T' is reached which I have to recognize. Then there could be an 'r', 's' or 't' followed by some values. Anyways I know how to recognize 'P' and then take in the 2 floats but then I know I have to have a while loop for the X and Y coordinates which will stop when I get to a 'T'. I do not know enough about C++ to make the loop stop and

I've seen both of these two for statements: for(i=0;i<10;i++) for(i=0;i!=10;i++) I know they all stop when i reaches 10 , but it seems better to use the second one (I heard). What is the different?I also want to know when use iterator to access member of a vector, what is the difference between iterator condition < vec.end() and != vec.end() for(i = start; i != end; ++i) This is the "standard" iterator loop. It has the advantage that it works with both pointers and standard library iterators (you can't rely on iterators having operator< defined). for(i = start; i < end; ++i) This won't work

I recently posed this question and thankfully was pointed to withRestarts() which seems pretty awesome and powerful to me :-) Now I'm eager to understand R's error handling capabilities in a bit more detail. Actual questions What is the recommended usage of simpleCondition() ? Never used it before, but I thought it might be useful for designing custom errors and warnings that are in fact "true" conditions. Could it be used to build a database of specific conditions for which specific handlers are available? Is there a way to "freeze" a certain state of the entire R workspace and return to it

I have a few loops that I need in my program. I can write out the pseudo code but I'm not entirely sure how to write them logically. I need - if (num is a multiple of 10) { do this } if (num is within 11-20, 31-40, 51-60, 71-80, 91-100) { do this } else { do this } //this part is for 1-10, 21-30, 41-50, 61-70, 81-90 This is for a snakes and ladders board game, if it makes any more sense for my question. I imagine the first if statement I'll need to use modulus, would if (num == 100%10) be correct? The second one I have no idea. I can write it out like if (num > 10 && num is < 21 || etc) but