370-Week 08

Week 08/id_370/Leetcode_205_370.java

@@ -0,0 +1,13 @@
+class Solution {
+    public boolean isIsomorphic(String s, String t) {
+	char[] ch1 = s.toCharArray();
+	char[] ch2 = t.toCharArray();
+	int len = s.length();
+	for (int i = 0; i < len; i++) {
+	    if(s.indexOf(ch1[i]) != t.indexOf(ch2[i])){
+		return false;
+	    }
+	}
+	return true;
+    }
+}

Week 08/id_370/Leetcode_8_370.java

@@ -0,0 +1,13 @@
+class Solution {
+    public boolean isIsomorphic(String s, String t) {
+	char[] ch1 = s.toCharArray();
+	char[] ch2 = t.toCharArray();
+	int len = s.length();
+	for (int i = 0; i < len; i++) {
+	    if(s.indexOf(ch1[i]) != t.indexOf(ch2[i])){
+		return false;
+	    }
+	}
+	return true;a
+    }
+}

Week 08/id_370/Leetcode_91_370.java

@@ -0,0 +1,30 @@
+class Solution {
+    public int numDecodings(String s) {
+	if (s == null || s.length() == 0) {
+	    return 0;
+	}
+	int len = s.length();
+
+	int help = 1;
+	int res = 0;
+	if (s.charAt(len - 1) != '0') {
+	    res = 1;
+	}
+	for (int i = len - 2; i >= 0; i--) {
+	    if (s.charAt(i) == '0') {
+		help = res;
+		res = 0;
+		continue;
+	    }
+	    if ((s.charAt(i) - '0') * 10 + (s.charAt(i + 1) - '0') <= 26) {
+		res += help;
+		//help用来存储res以前的值
+		help = res-help;
+	    } else {
+		help = res;
+	    }
+
+	}
+	return res;
+    }
+}