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Commit 9f6af49

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feat: add solutions to lc problem: No.0306
No.0306.Additive Number
1 parent 67886c1 commit 9f6af49

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6 files changed

+420
-45
lines changed

6 files changed

+420
-45
lines changed

‎solution/0300-0399/0306.Additive Number/README.md‎

Lines changed: 146 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -34,22 +34,167 @@
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<!-- 这里可写通用的实现逻辑 -->
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DFS + 剪枝。
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Python 大整数相加不会有溢出问题。由于 num 字符串长度最大为 35,因此对于其他语言,可以通过控制整数长度防止溢出。
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3741
<!-- tabs:start -->
3842

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### **Python3**
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4145
<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
44-
48+
class Solution:
49+
def isAdditiveNumber(self, num: str) -> bool:
50+
def dfs(a, b, num):
51+
if not num:
52+
return True
53+
if a + b > 0 and num[0] == '0':
54+
return False
55+
for i in range(1, len(num) + 1):
56+
if a + b == int(num[:i]):
57+
if dfs(b, a + b, num[i:]):
58+
return True
59+
return False
60+
61+
n = len(num)
62+
for i in range(1, n - 1):
63+
for j in range(i + 1, n):
64+
if i > 1 and num[0] == '0':
65+
break
66+
if j - i > 1 and num[i] == '0':
67+
continue
68+
if dfs(int(num[:i]), int(num[i: j]), num[j:]):
69+
return True
70+
return False
4571
```
4672

4773
### **Java**
4874

4975
<!-- 这里可写当前语言的特殊实现逻辑 -->
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5177
```java
78+
class Solution {
79+
public boolean isAdditiveNumber(String num) {
80+
int n = num.length();
81+
for (int i = 1; i < Math.min(n - 1, 19); ++i) {
82+
for (int j = i + 1; j < Math.min(n, i + 19); ++j) {
83+
if (i > 1 && num.charAt(0) == '0') {
84+
break;
85+
}
86+
if (j - i > 1 && num.charAt(i) == '0') {
87+
continue;
88+
}
89+
long a = Long.parseLong(num.substring(0, i));
90+
long b = Long.parseLong(num.substring(i, j));
91+
if (dfs(a, b, num.substring(j))) {
92+
return true;
93+
}
94+
}
95+
}
96+
return false;
97+
}
98+
99+
private boolean dfs(long a, long b, String num) {
100+
if ("".equals(num)) {
101+
return true;
102+
}
103+
if (a + b > 0 && num.charAt(0) == '0') {
104+
return false;
105+
}
106+
for (int i = 1; i < Math.min(num.length() + 1, 19); ++i) {
107+
if (a + b == Long.parseLong(num.substring(0, i))) {
108+
if (dfs(b, a + b, num.substring(i))) {
109+
return true;
110+
}
111+
}
112+
}
113+
return false;
114+
}
115+
}
116+
```
117+
118+
### **C++**
119+
120+
```cpp
121+
class Solution {
122+
public:
123+
bool isAdditiveNumber(string num) {
124+
int n = num.size();
125+
for (int i = 1; i < min(n - 1, 19); ++i)
126+
{
127+
for (int j = i + 1; j < min(n, i + 19); ++j)
128+
{
129+
if (i > 1 && num[0] == '0') break;
130+
if (j - i > 1 && num[i] == '0') continue;
131+
auto a = stoll(num.substr(0, i));
132+
auto b = stoll(num.substr(i, j - i));
133+
if (dfs(a, b, num.substr(j, n - j))) return true;
134+
}
135+
}
136+
return false;
137+
}
138+
139+
bool dfs(long long a, long long b, string num) {
140+
if (num == "") return true;
141+
if (a + b > 0 && num[0] == '0') return false;
142+
for (int i = 1; i < min((int) num.size() + 1, 19); ++i)
143+
if (a + b == stoll(num.substr(0, i)))
144+
if (dfs(b, a + b, num.substr(i, num.size() - i)))
145+
return true;
146+
return false;
147+
}
148+
};
149+
```
52150

151+
### **Go**
152+
153+
```go
154+
func isAdditiveNumber(num string) bool {
155+
n := len(num)
156+
var dfs func(a, b int64, num string) bool
157+
dfs = func(a, b int64, num string) bool {
158+
if num == "" {
159+
return true
160+
}
161+
if a+b > 0 && num[0] == '0' {
162+
return false
163+
}
164+
for i := 1; i < min(len(num)+1, 19); i++ {
165+
c, _ := strconv.ParseInt(num[:i], 10, 64)
166+
if a+b == c {
167+
if dfs(b, c, num[i:]) {
168+
return true
169+
}
170+
}
171+
}
172+
return false
173+
}
174+
for i := 1; i < min(n-1, 19); i++ {
175+
for j := i + 1; j < min(n, i+19); j++ {
176+
if i > 1 && num[0] == '0' {
177+
break
178+
}
179+
if j-i > 1 && num[i] == '0' {
180+
continue
181+
}
182+
a, _ := strconv.ParseInt(num[:i], 10, 64)
183+
b, _ := strconv.ParseInt(num[i:j], 10, 64)
184+
if dfs(a, b, num[j:]) {
185+
return true
186+
}
187+
}
188+
}
189+
return false
190+
}
191+
192+
func min(a, b int) int {
193+
if a < b {
194+
return a
195+
}
196+
return b
197+
}
53198
```
54199

55200
### **...**

‎solution/0300-0399/0306.Additive Number/README_EN.md‎

Lines changed: 142 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -49,13 +49,154 @@ How would you handle overflow for very large input integers?</p>
4949
### **Python3**
5050

5151
```python
52-
52+
class Solution:
53+
def isAdditiveNumber(self, num: str) -> bool:
54+
def dfs(a, b, num):
55+
if not num:
56+
return True
57+
if a + b > 0 and num[0] == '0':
58+
return False
59+
for i in range(1, len(num) + 1):
60+
if a + b == int(num[:i]):
61+
if dfs(b, a + b, num[i:]):
62+
return True
63+
return False
64+
65+
n = len(num)
66+
for i in range(1, n - 1):
67+
for j in range(i + 1, n):
68+
if i > 1 and num[0] == '0':
69+
break
70+
if j - i > 1 and num[i] == '0':
71+
continue
72+
if dfs(int(num[:i]), int(num[i: j]), num[j:]):
73+
return True
74+
return False
5375
```
5476

5577
### **Java**
5678

5779
```java
80+
class Solution {
81+
public boolean isAdditiveNumber(String num) {
82+
int n = num.length();
83+
for (int i = 1; i < Math.min(n - 1, 19); ++i) {
84+
for (int j = i + 1; j < Math.min(n, i + 19); ++j) {
85+
if (i > 1 && num.charAt(0) == '0') {
86+
break;
87+
}
88+
if (j - i > 1 && num.charAt(i) == '0') {
89+
continue;
90+
}
91+
long a = Long.parseLong(num.substring(0, i));
92+
long b = Long.parseLong(num.substring(i, j));
93+
if (dfs(a, b, num.substring(j))) {
94+
return true;
95+
}
96+
}
97+
}
98+
return false;
99+
}
100+
101+
private boolean dfs(long a, long b, String num) {
102+
if ("".equals(num)) {
103+
return true;
104+
}
105+
if (a + b > 0 && num.charAt(0) == '0') {
106+
return false;
107+
}
108+
for (int i = 1; i < Math.min(num.length() + 1, 19); ++i) {
109+
if (a + b == Long.parseLong(num.substring(0, i))) {
110+
if (dfs(b, a + b, num.substring(i))) {
111+
return true;
112+
}
113+
}
114+
}
115+
return false;
116+
}
117+
}
118+
```
119+
120+
### **C++**
121+
122+
```cpp
123+
class Solution {
124+
public:
125+
bool isAdditiveNumber(string num) {
126+
int n = num.size();
127+
for (int i = 1; i < min(n - 1, 19); ++i)
128+
{
129+
for (int j = i + 1; j < min(n, i + 19); ++j)
130+
{
131+
if (i > 1 && num[0] == '0') break;
132+
if (j - i > 1 && num[i] == '0') continue;
133+
auto a = stoll(num.substr(0, i));
134+
auto b = stoll(num.substr(i, j - i));
135+
if (dfs(a, b, num.substr(j, n - j))) return true;
136+
}
137+
}
138+
return false;
139+
}
140+
141+
bool dfs(long long a, long long b, string num) {
142+
if (num == "") return true;
143+
if (a + b > 0 && num[0] == '0') return false;
144+
for (int i = 1; i < min((int) num.size() + 1, 19); ++i)
145+
if (a + b == stoll(num.substr(0, i)))
146+
if (dfs(b, a + b, num.substr(i, num.size() - i)))
147+
return true;
148+
return false;
149+
}
150+
};
151+
```
58152

153+
### **Go**
154+
155+
```go
156+
func isAdditiveNumber(num string) bool {
157+
n := len(num)
158+
var dfs func(a, b int64, num string) bool
159+
dfs = func(a, b int64, num string) bool {
160+
if num == "" {
161+
return true
162+
}
163+
if a+b > 0 && num[0] == '0' {
164+
return false
165+
}
166+
for i := 1; i < min(len(num)+1, 19); i++ {
167+
c, _ := strconv.ParseInt(num[:i], 10, 64)
168+
if a+b == c {
169+
if dfs(b, c, num[i:]) {
170+
return true
171+
}
172+
}
173+
}
174+
return false
175+
}
176+
for i := 1; i < min(n-1, 19); i++ {
177+
for j := i + 1; j < min(n, i+19); j++ {
178+
if i > 1 && num[0] == '0' {
179+
break
180+
}
181+
if j-i > 1 && num[i] == '0' {
182+
continue
183+
}
184+
a, _ := strconv.ParseInt(num[:i], 10, 64)
185+
b, _ := strconv.ParseInt(num[i:j], 10, 64)
186+
if dfs(a, b, num[j:]) {
187+
return true
188+
}
189+
}
190+
}
191+
return false
192+
}
193+
194+
func min(a, b int) int {
195+
if a < b {
196+
return a
197+
}
198+
return b
199+
}
59200
```
60201

61202
### **...**
Lines changed: 28 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,28 @@
1+
class Solution {
2+
public:
3+
bool isAdditiveNumber(string num) {
4+
int n = num.size();
5+
for (int i = 1; i < min(n - 1, 19); ++i)
6+
{
7+
for (int j = i + 1; j < min(n, i + 19); ++j)
8+
{
9+
if (i > 1 && num[0] == '0') break;
10+
if (j - i > 1 && num[i] == '0') continue;
11+
auto a = stoll(num.substr(0, i));
12+
auto b = stoll(num.substr(i, j - i));
13+
if (dfs(a, b, num.substr(j, n - j))) return true;
14+
}
15+
}
16+
return false;
17+
}
18+
19+
bool dfs(long long a, long long b, string num) {
20+
if (num == "") return true;
21+
if (a + b > 0 && num[0] == '0') return false;
22+
for (int i = 1; i < min((int) num.size() + 1, 19); ++i)
23+
if (a + b == stoll(num.substr(0, i)))
24+
if (dfs(b, a + b, num.substr(i, num.size() - i)))
25+
return true;
26+
return false;
27+
}
28+
};

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