Problem:
Score : 100 points

Problem Statement

There is an N-car train.

You are given an integer i. Find the value of j such that the following statement is true: "the i-th car from the front of the train is the j-th car from the back."

Constraints

1 \leq N \leq 100

1 \leq i \leq N

Input

Input is given from Standard Input in the following format:

N i

Output

Print the answer.

Sample Input 1

4 2

Sample Output 1

3

The second car from the front of a 4-car train is the third car from the back.

Sample Input 2

1 1

Sample Output 2

1

Sample Input 3

15 11

Sample Output 3

5

Solution in C (GCC 5.4.1) (judge verdict: Accepted)

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<math.h>

#define MAX(p,q) ((p>q)?(p):(q))
#define MIN(p,q) ((p<q)?(p):(q))

#define REP(i,n) for(i=0;i<n;i++)

int gcd(int a,int b);

int main(void)
{
  int n,i;
  scanf("%d%d",&n,&i);
  printf("%d",n-i+1);
}

int gcd(int a,int b)
{
  int max,min,tmp;
  max = MAX(a,b);
  min = MIN(a,b);
  if(max%min==0) return min;
  else
  {
    tmp = min;
    min = max%min;
    max = tmp;
    return gcd(max,min);
  }
}