两种不同输入的交替字符

Question

我想采取两个字符串和交替的字符到一个新的字符串使用for方法。

例如：“两个”和“一个”

结果：“townoe”

这就是我到目前为止所拥有的，我真的不知道如何完成它。

public class Alternator {   
    String alternate(String a, String b) {
        String s = "";
        for (int i = 0; i < a.length(); i++) {
            s += i;
            System.out.println(s);
        }
        return null;
    }
}

Answer 1

这将工作，如果字符串是相同的长度或不同的长度。

static void mergeStrings(String a, String b) {
    StringBuilder mergedBuilder = new StringBuilder();
    char[] aCharArr = a.toCharArray();
    char[] bCharArr = b.toCharArray();

    int minLength = aCharArr.length >= bCharArr.length ? bCharArr.length : aCharArr.length;

    for (int i=0; i<minLength; i++) {
        mergedBuilder.append(aCharArr[i]).append(bCharArr[i]);
    }

    if(minLength < aCharArr.length) {
        mergedBuilder.append(a.substring(minLength));
    }
    else{
        mergedBuilder.append(b.substring(minLength));
    }
    Systemout.println(mergedBuilder.toString());
}

Answer 2

这里有一些紧凑的方法来做到这一点：

String alternate(String a, String b) {
    StringBuilder builder = new StringBuilder();

    int smallerStringLength = Math.min(a.length(), b.length());
    for (int i = 0; i < smallerStringLength; i++) {
        builder.append(a.charAt(i));
        builder.append(b.charAt(i));
    }
    return builder.toString();
}

或者更优化：

String alternate(String first, String second) {
    char[] firstChars = first.toCharArray();
    char[] secondChars = second.toCharArray();

    int smallerCharsCount = Math.min(firstChars.length, secondChars.length);
    StringBuilder builder = new StringBuilder(smallerCharsCount * 2);
    for (int i = 0; i < smallerCharsCount; i++) {
        builder.append(firstChars[i]);
        builder.append(secondChars[i]);
    }
    return builder.toString();
}

Answer 3

public class Alternator{
    public static String alternate(String a, String b){
        String s = "";
        int i = 0;
        while (i < a.length() && i < b.length()){
            s += a.charAt(i) +""+ b.charAt(i); 
            i++;
        }
        while (i < a.length() ){
            s += a.charAt(i); 
            i++;
        }
        while (i < b.length()){
            s += b.charAt(i); 
            i++;
        }
        return s;
    }
    public static void main(String[] args){
        String a = "two", b = "one";
        String s = Alternator.alternate(a,b);
        System.out.println(s);
    }
}

要使用for循环而不是而循环，只需像下面这样删除所有的而行，然后从每个而循环中删除i行

for(; i < a.length() && i < b.length(); i++){
//the inside of the loop MINUS THE LINE i++ 
}
for(; i < a.length(); i++){
//the inside of the loop MINUS THE LINE i++ 
}
for(; i < b.length(); i++){
//the inside of the loop MINUS THE LINE i++ 
}