```go
package main

import (
	"fmt"
)

func check(k, p int) bool {
	i := k % 475
	for j := 0; j < 25; j++ {
		i = (i*96 + 42) % 475
		if 26+i == p {
			return true
		}
	}
	return false
}

func main() {
	var p, x, y int
	if _, err := fmt.Scan(&p, &x, &y); err != nil {
		return
	}

	k_min := 0
	if y > x%50 {
		k_min = (y - x%50 + 49) / 50
	}

	for k := k_min; ; k++ {
		if check(k, p) {
			u := 0
			if k > x/50 {
				u = (k - x/50 + 1) / 2
			}
			fmt.Println(u)
			return
		}
	}
}
```