/*
 * Copyright (C) 2014 Pedro Vicente Gómez Sánchez.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.github.pedrovgs.problem32;

/**
 * Given two strings passed as argument, can you write a method to return true if the second
 * contains the first one?
 *
 * @author Pedro Vicente Gómez Sánchez.
 */
public class Contains {

  public boolean evaluate(String word1, String word2) {
    return false;
  }
}

/*
 * Copyright (C) 2014 Pedro Vicente Gómez Sánchez.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.github.pedrovgs.problem32;

/**
 * Given two strings passed as argument, can you write a method to return true if the second
 * contains the first one?
 *
 * @author Pedro Vicente Gómez Sánchez.
 */
public class Contains {

  /**
   * Iterative solution to this problem. The complexity order of this algorithm is O(N*M) where N
   * is the length of the first word and M is the length of the second word. In space terms the
   * complexity order of this algorithm is O(1) because we are not using any auxiliary data
   * structure to solve this problem.
   */
  public boolean evaluate(String w1, String w2) {
    if (w1 == null || w2 == null) {
      throw new IllegalArgumentException("You can't pass null strings as input.");
    }
    boolean contains = false;
    for (int i = 0; i < w2.length() - 1; i++) {
      if (w2.charAt(i) == w1.charAt(0)) {
        for (int j = 0; j < w1.length(); j++) {
          if (w1.charAt(j) == w2.charAt(i + j) && j == w1.length() - 1) {
            contains = true;
            break;
          }
        }
      }
    }
    return contains;
  }
}

Add iterative solution to problem 32