CodeForces 25A IQ test 唯一奇偶

原題： http://codeforces.com/problemset/problem/25/A

題目：

IQ test

time limit per test2 seconds

memory limit per test256 megabytes

inputstandard input

outputstandard output

Bob is preparing to pass IQ test. The most frequent task in this test is to find out which one of the given n numbers differs from the others. Bob observed that one number usually differs from the others in evenness. Help Bob — to check his answers, he needs a program that among the given n numbers finds one that is different in evenness.

Input

The first line contains integer n (3 ≤ n ≤ 100) — amount of numbers in the task. The second line contains n space-separated natural numbers, not exceeding 100. It is guaranteed, that exactly one of these numbers differs from the others in evenness.

Output

Output index of number that differs from the others in evenness. Numbers are numbered from 1 in the input order.

Sample test(s)

input

5

2 4 7 8 10

output

3

input

4

1 2 1 1

output

2

思路：

一組數隻有一個奇數或者偶數，輸出它的位置。

每次記錄最後一個奇數或者偶數的位置，并對奇偶計數，計數為1的就是要輸出數的類型。

代碼：

#include <iostream>
#include"cstdio"
#include"string.h"
#include"vector"
using namespace std;

const int N = ;
int a[N];
int n;

int main()
{
    //freopen("in.txt","r",stdin);
    while(scanf("%d",&n)!=EOF)
    {
        int flag1;
        int flag2;
        int ans1=;
        int ans2=;
        for(int i=; i<=n; i++)
        {
            scanf("%d",&a[i]);
            if(a[i]%==)
            {
                flag1=i;
                ans1++;
            }
            else
            {
                flag2=i;
                ans2++;
            }
        }
        if(ans1&&ans2)
        {
            if(ans1==)
                printf("%d\n",flag1);
            else
                printf("%d\n",flag2);
        }
    }
    return ;
}