Codeforces Round #384 (Div. 2) A. Vladik and flights

A. Vladik and flights
time limit per test2 seconds
memory limit per test256 megabytes
inputstandard input
outputstandard output
Vladik is a competitive programmer. This year he is going to win the International Olympiad in Informatics. But it is not as easy as it sounds: the question Vladik face now is to find the cheapest way to get to the olympiad.

Vladik knows n airports. All the airports are located on a straight line. Each airport has unique id from 1 to n, Vladik’s house is situated next to the airport with id a, and the place of the olympiad is situated next to the airport with id b. It is possible that Vladik’s house and the place of the olympiad are located near the same airport.

To get to the olympiad, Vladik can fly between any pair of airports any number of times, but he has to start his route at the airport a and finish it at the airport b.

Each airport belongs to one of two companies. The cost of flight from the airport i to the airport j is zero if both airports belong to the same company, and |i - j| if they belong to different companies.

Print the minimum cost Vladik has to pay to get to the olympiad.

Input
The first line contains three integers n, a, and b (1 ≤ n ≤ 105, 1 ≤ a, b ≤ n) — the number of airports, the id of the airport from which Vladik starts his route and the id of the airport which he has to reach.

The second line contains a string with length n, which consists only of characters 0 and 1. If the i-th character in this string is 0, then i-th airport belongs to first company, otherwise it belongs to the second.

Output
Print single integer — the minimum cost Vladik has to pay to get to the olympiad.

Examples
input
4 1 4
1010
output
1
input
5 5 2
10110
output
0
Note
In the first example Vladik can fly to the airport 2 at first and pay |1 - 2| = 1 (because the airports belong to different companies), and then fly from the airport 2 to the airport 4 for free (because the airports belong to the same company). So the cost of the whole flight is equal to 1. It’s impossible to get to the olympiad for free, so the answer is equal to 1.

In the second example Vladik can fly directly from the airport 5 to the airport 2, because they belong to the same company.

题意：一个人坐飞机去某地。有两个航空公司，用1和0表示，如果两个地点同样是1或同样是0，表示都是自家航空公司，坐飞机不用钱。否则要花费1。问到达目的地最小花费。输入有n个地点，以及从a地去b地，a b为序列的下标。

题解：如果出发地和目的地是同一家公司花费就是0，如果不是同一家公司，就直接免费飞到离目的地公司最近的地点，换乘，花费1后直接免费飞到目的地，也就是说，最多花费1，公司不同就花费1。

#include<stdio.h>///若出发点和终点的公司一样则花费为0，不一样则花费为1
#include<string.h>
#include<algorithm>
using namespace std;
int main()
{
    int n,a,b,i;
    char str[100005];
    while(scanf("%d%d%d",&n,&a,&b)!=EOF)
    {
        scanf("%s",str);
        int st=str[a-1]-'0';
        int ed=str[b-1]-'0';
        if(st!=ed)
        {
           printf("1\n");
        }
        else
            printf("0\n");
    }
}