//Count Divisors
// Sample code to perform I/O:

process.stdin.resume();
process.stdin.setEncoding("utf-8");
var stdin_input = "";

process.stdin.on("data", function (input) {
    stdin_input += input;                               // Reading input from STDIN
});

process.stdin.on("end", function () {
   main(stdin_input);
});

function main(input) {
    const data= input.toString().split("\n");
    
    console.log(divisors(data[0]));       // Writing output to STDOUT
}

// Warning: Printing unwanted or ill-formatted data to output will cause the test cases to fail



// Write your code here
// Sample code to perform I/O:
//Enter your code here

function divisors(s) {
    
    var arr = s.split(" ").map(item => Number(item));
    
    
    const l = arr[0];
    const r = arr[1];

    const k = arr[2];

    
    var count =0;

    for (var i=l; i<=r; i++) {
        if ((i % k)==0) count++
        
    }
    
    return count; 
    
}