Program not returning

Question

i want to find a "peak value" in an array (a value where a1 ai+1>...>an, ai being the peak value here). I am using divide and conquer for a more optimum solution here. For" 6 1 3 50 70 100 48", it will print "70 100 48 4" which is good ( 70 < 100 and 100 > 48) but it does not return Integer.toString(a[m]), it returns "Array has no peak". I tried removing string and working with int but i get the exact same issue.

public class Main {

    public int n, a[];

    void read() {
        File file = new File("src/com/fmi/Vector.txt");
        Scanner sc;

        try {
            sc = new Scanner(file);
            int i = 0;
            if (sc.hasNextInt()) {
                n = sc.nextInt();
            }
            a = new int[n];
            while (sc.hasNextInt()) {
                int aux = sc.nextInt();
                a[i] = aux;
                i++;
            }
        } catch (FileNotFoundException e) {
            System.out.println("File not found!");
        }
    }

    String search(int p, int u) {
        int m;
        System.out.println(p + " " + u);
        if (p == u) {
            return "0";
        } else {
            m = (p + u) / 2;
            System.out.println(a[m - 1] + " " + a[m] + " " + a[m + 1] + " " + m);
            if (a[m - 1] < a[m] && a[m] > a[m + 1]) {
                return Integer.toString(a[m]);
            } else if (a[m - 1] < a[m] && a[m] < a[m + 1]) {
                search(m, u);
            } else if (a[m - 1] > a[m] && a[m] > a[m + 1]) {
                search(p, m);
            }
        }
        return "Array has no peak!";
    }

    void display() {
        for (int i = 0; i < n; i++) {
            System.out.print(a[i] + " ");
        }
        System.out.println(" ");
        for (int i = 0; i < n; i++) {
            System.out.print(i + " ");
        }
    }

    public static void main(String[] args) {
        Main obj = new Main();
        obj.read();
        System.out.println(obj.search(0, obj.n));
        obj.display();
    }
}

Answer 1

You're calling search but you're not doing anything with the result. You should do something like

return search(m,u);