Frog Jump Solution

A small frog wants to get to the other side of the road. The frog is currently located at position X and wants to get to a position greater than or equal to Y. The small frog always jumps a fixed distance, D.

Count the minimal number of jumps that the small frog must perform to reach its target.

Write a function:

1
2function solution(X, Y, D) {
3  // write your code in JavaScript (Node.js 8.9.4)
4}
5

that, given three integers X, Y and D, returns the minimal number of jumps from position X to a position equal to or greater than Y.

For example, given:

X = 10
Y = 85
D = 30

the function should return 3, because the frog will be positioned as follows:

after the first jump, at position 10 + 30 = 40
after the second jump, at position 10 + 30 + 30 = 70
after the third jump, at position 10 + 30 + 30 + 30 = 100

Write an efficient algorithm for the following assumptions:

X, Y and D are integers within the range [1..1,000,000,000];
X ≤ Y.

1
2function solution(x, y, d) {
3    // write your code in JavaScript (Node.js 8.9.4)
4    if ((y - x) % d === 0) {
5       return (y - x) / d;
6    }
7    return Math.ceil((y - x) / d);
8}
9

Points to be Taken

Solution need division check with modulo operator whether its remainder is zero.