Problem:
Score : 100 points

Problem Statement

It has been decided that a programming contest sponsored by company A will be held, so we will post the notice on a bulletin board.

The bulletin board is in the form of a grid with N rows and N columns, and the notice will occupy a rectangular region with H rows and W columns.

How many ways are there to choose where to put the notice so that it completely covers exactly HW squares?

Constraints

1 \leq H, W \leq N \leq 100

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
H
W

Output

Print the answer.

Sample Input 1

3
2
3

Sample Output 1

2

There are two ways to put the notice, as follows:

### ...
### ###
... ###

Here, # represents a square covered by the notice, and . represents a square not covered.

Sample Input 2

100
1
1

Sample Output 2

10000

Sample Input 3

5
4
2

Sample Output 3

8

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <stdio.h>

int root_check(int h, int w, char s[h][w+1], int start_x, int start_y, int gole_x, int gole_y, int visit[h][w+1]){
   
    if(visit[start_x][start_y])
        return 0;
    visit[start_x][start_y] = 1;
    if(start_x == gole_x && start_y == gole_y)
        return 1;
    if(start_x > 0 && s[start_x][start_y] != s[start_x-1][start_y]){
        if(root_check(h, w, s, start_x-1, start_y, gole_x, gole_y, visit))
            return 1;
    }
    if(start_x < h-1 && s[start_x][start_y] != s[start_x+1][start_y]){
        if(root_check(h, w, s, start_x+1, start_y, gole_x, gole_y, visit))
            return 1;
    }
    if(start_y > 0 && s[start_x][start_y] != s[start_x][start_y-1]){
        if(root_check(h, w, s, start_x, start_y-1, gole_x, gole_y, visit))
            return 1;
    }
    if(start_y < w-1 && s[start_x][start_y] != s[start_x][start_y+1]){
        if(root_check(h, w, s, start_x, start_y+1, gole_x, gole_y, visit))
            return 1;
    }
    return 0;
}

int black_white(int h, int w, char s[h][w+1], int x, int y){
    int count = 0;
    int i, j;
    int visit[h][w+1];

    for(i = 0; i < h;i++){
        //printf("\n");
        for(j = 0; j < w; j++){
           // printf("%c", s[i][j]);
            if(s[i][j] == '.'){
               // printf("%d %d\n", i,j);
                for(int a=0;a<h;a++)
                    for(int b=0;b<=w; b++)
                        visit[a][b] = 0;    
                count += root_check(h, w, s, x, y, i, j, visit);
               // printf("(%d %d)(%d %d) %d\n",x, y,i,j,count);
            }
        }
    }
    return count;
}

int count_root(int h, int w, char s[h][w+1]){
    int i, j, count = 0;
    for(i = 0; i < h;i++){
        for(j = 0; j < w; j++){
            if(s[i][j] == '#'){
                count += black_white(h, w, s, i, j);
            }
        }
    }

    return count;
}

int main(){
    int h, w, i;
    scanf("%d%d", &h, &w);
    char s[h][w+1];
    
    for(i = 0; i < h; i++){
        scanf("%s", s[i]);
    }
    int black;

    printf("%d\n",count_root(h, w, s));
    return 0;
}