objective c - ObjC: scanf skipped in do/while loop -

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i'm starting teach myself objective c , have been fooling around simple console based calculator. start i'm asking user operation perform, 2 numbers perform operation on, , print answer after it's calculated.

that part seems work fine - next piece i'm trying implement allow user keep making calculations until decide no longer want to. thinking approach put running of calculator inside do/while loop @ end of checking see if user wants continue via 'y' or 'no' via scanf();, , check see user choose respond with. i'm encountering though @ end of first pass, request input via scanf(); gets ignored , program terminates.

i hoping :) i've done due diligence best via troubleshooting, online research(found on white space issue scanf(); didn't help), , guessing date i've been unsuccessful. below main section of code:

int main (int argc, const char * argv[]) {     nsautoreleasepool * pool = [[nsautoreleasepool alloc] init];       float answer;     char op,repeat;     nslog(@"welcome sexy calculater, (_(_)!!"); //don't mind me being weird      calculater *deskcalc;        deskcalc=[[calculater alloc] init];          {          [deskcalc clear];//clear calc          op =[deskcalc getoperator]; //get +,-,*,or/         [deskcalc getnumbers]; //get 2 numbers          [deskcalc calculate: op];         answer=[deskcalc accumulater];          nslog(@"your answer %f!", answer);           nslog(@"would calculate again(y/n)?");         scanf("%c",&repeat);         //nslog(@"you typed: %c", repeat);      } while (repeat=='y');      [deskcalc release];      [pool drain];     return 0; }

thanks in advance help. if haven't provided enough information apologize! please let me know , i'll more willing provide more. again all!

you want have @ scanf skips every other while loop in c

you need work ensure scanf() read newline that's on stdin after user enter 'y', 'n', or whatever other streams of keys hit before pressing enter.

this other posting seems relevant: why scanf() causing infinite loop in code?


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