Processing strings

# Topic

String

# Problem

Number of occurrences

Write a program that finds the frequency of occurrences of a substring in a given string. Substrings cannot overlap: for example, the string ababa contains only one substring aba.

Input data format

The first input line contains a string, the second one contains a substring.

Sample Input 1:

ababa
aba

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2

Sample Output 1:

Sample Input 2:

hello there
the

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2

Sample Output 2:

Sample Input 3:

hello yellow jello
ll

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2

Sample Output 3:

# Hint & Explain

Check out the indexOf(String str, int formIndex) method.

# Solution

# My solution

import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        // put your code here
        Scanner scanner = new Scanner(System.in);
        String string = scanner.nextLine();
        String subString = scanner.nextLine();
        int fromIndex = 0;
        int occurIndex;
        int counter = 0;

        do {
            if (fromIndex > string.length() - 1) {
                break;
            }
            occurIndex = string.indexOf(subString, fromIndex);
            if (occurIndex != -1) {
                counter++;
                fromIndex = occurIndex + subString.length();
            }
        } while (occurIndex != -1);

        System.out.println(counter);

    }
}

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# Other solution 1

import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        // put your code here
        Scanner scanner = new Scanner(System.in);
        String sentence = " " + scanner.nextLine() + " ";
        String query = scanner.nextLine().trim();
        System.out.print(sentence.split(query).length - 1);
    }
}

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# Other solution 2

import java.util.Scanner;

class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String string = scanner.nextLine();
        String substring = scanner.nextLine();
        System.out.println((string.length() - string.replace(substring, "").length()) / substring.length());
    }
}

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编辑

上次更新: 2023/04/14, 12:58:00

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