//main logic

#include <stdio.h>
#include <map>
#include <iostream>
using namespace std;

map<int, bool>  exist;
map<int, bool>  odd;
map<int, int>  prev;

bool add(int a, int b,  bool c){//b>=a;
    if (!exist[b]){
      exist[b] = true;
      odd[b] = c;
      prev[b] = a;
      return true;
    };
    int  i = prev[b];
    if(i==a) return (odd[b]==c);
    if(i<a) return add(i,a-1, (c!=odd[b]));
    return add(a,i-1, (c!=odd[b]));
};

Thank you very much, at least I solved it!
Nice problem!

thank you! i study very from you

Thanks! nice idea ;) I've got AC thank you very much!!!)

Edited by author 01.11.2011 17:53

100
5
5 6 odd
7 8 odd
1 6 even
1 4 odd
7 8 even

why result is 3 and not 4?

because 1 1 = 0 but 0 0 not 1

the input format is verrrry misleading, i have lost 2 hours of my live because of it.

#include <stdio.h>
#include <map>
#include <iostream>
#include <string>
using namespace std;

map<int, bool>  exist;
map<int, bool>  odd;
map<int, int>  previous;

bool add(int a, int b,  bool c){//b>=a;
    if (!exist[b]){
      exist[b] = true;
      odd[b] = c;
      previous[b] = a;
      return true;
    };
    int  i = previous[b];
    if(i==a) return (odd[b]==c);
    if(i<a) return add(i,a-1, (c!=odd[b]));
    return add(a,i-1, (c!=odd[b]));
};

int main(int argc, char * argv[]) {
    while (1) {
        exist.clear();
        odd.clear();
        previous.clear();
        int numbers = 0;
        cin >> numbers;
        if (numbers==-1) break;
        int questions = 0;
        cin >> questions;
        bool flag = false;
        for (int i = 0; i<questions; i++) {
            int a = 0;
            cin >> a;
            int b = 0;
            cin >> b;
            string tmp;
            cin >> tmp;
            bool parity = false;
            if (tmp=="even") {
                parity = true;
            }
            if ((add(a,b,parity)==false)&&(flag==false)) {
                cout << i;
                flag=true;
            }
        }
        if (flag==false) {
            cout << questions;
        }
    }
    return 0;
}

What wrong? I got wa at 1 test.

Then run it in the debug mode and you'll figure it out.

changeto
            bool parity = true;
            if (tmp=="even") {
                parity = false;
            }
and then break after flag=true;

Edited by author 21.03.2012 22:25

Edited by author 21.03.2012 22:25

{
100
5
5 6 odd
7 8 odd
1 6 even
1 4 odd
7 8 even

why result is 3 and not 4?
}
I think the answer is 4, because [1,4] is odd and [5,6] is odd and [1,4],[5,6] are continuous then the answer isn't 3, but it is 4.

Edited by author 02.05.2012 15:37

Edited by author 02.05.2012 15:40

Edited by author 02.05.2012 15:40

Thanks a lot!

Good programing skills!! Thanks~

remarkable code.

Pretty well!

:0 this approach is out of my mind, great work!!