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Commit fbfd3dc

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feat: add solutions to lc problem: No.0367
No.0367.Valid Perfect Square
1 parent cad24b1 commit fbfd3dc

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8 files changed

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-45
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8 files changed

+123
-45
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‎solution/0000-0099/0052.N-Queens II/README.md‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -15,7 +15,7 @@
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<div class="original__bRMd">
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<div>
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<p><strong>示例 1:</strong></p>
18-
<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/queens.jpg" style="width: 600px; height: 268px;" />
18+
<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/8-queens.png" style="width: 600px; height: 268px;" />
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<pre>
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<strong>输入:</strong>n = 4
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<strong>输出:</strong>2

‎solution/0000-0099/0052.N-Queens II/README_EN.md‎

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@@ -10,7 +10,7 @@
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<p>&nbsp;</p>
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<p><strong>Example 1:</strong></p>
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<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/queens.jpg" style="width: 600px; height: 268px;" />
13+
<img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0052.N-Queens%20II/images/8-queens.png" style="width: 600px; height: 268px;" />
1414
<pre>
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<strong>Input:</strong> n = 4
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<strong>Output:</strong> 2

‎solution/0300-0399/0367.Valid Perfect Square/README.md‎

Lines changed: 57 additions & 15 deletions
Original file line numberDiff line numberDiff line change
@@ -38,7 +38,11 @@
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<!-- 这里可写通用的实现逻辑 -->
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二分法。
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**1. 二分查找**
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43+
**2. 转换为数学问题**
44+
45+
由于 `n2 = 1 + 3 + 5 + ... + (2n-1)`,对数字 num 不断减去 i (`i = 1, 3, 5, ...`) 直至 num 不大于 0,如果最终 num 等于 0,说明是一个有效的完全平方数。
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<!-- tabs:start -->
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@@ -51,25 +55,35 @@ class Solution:
5155
def isPerfectSquare(self, num: int) -> bool:
5256
left, right = 1, num
5357
while left < right:
54-
mid = left + ((right- left) >> 1)
55-
if num // mid <= mid:
58+
mid = (left + right) >> 1
59+
if mid * mid >= num:
5660
right = mid
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else:
5862
left = mid + 1
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return left * left == num
6064
```
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```python
67+
class Solution:
68+
def isPerfectSquare(self, num: int) -> bool:
69+
i = 1
70+
while num > 0:
71+
num -= i
72+
i += 2
73+
return num == 0
74+
```
75+
6276
### **Java**
6377

6478
<!-- 这里可写当前语言的特殊实现逻辑 -->
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6680
```java
6781
class Solution {
6882
public boolean isPerfectSquare(int num) {
69-
int left = 1, right = num;
83+
long left = 1, right = num;
7084
while (left < right) {
71-
int mid = (left + right) >>> 1;
72-
if (num / mid <= mid) {
85+
long mid = (left + right) >>> 1;
86+
if (mid * mid >= num) {
7387
right = mid;
7488
} else {
7589
left = mid + 1;
@@ -80,34 +94,53 @@ class Solution {
8094
}
8195
```
8296

97+
```java
98+
class Solution {
99+
public boolean isPerfectSquare(int num) {
100+
for (int i = 1; num > 0; i += 2) {
101+
num -= i;
102+
}
103+
return num == 0;
104+
}
105+
}
106+
```
107+
83108
### **C++**
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85110
```cpp
86111
class Solution {
87112
public:
88113
bool isPerfectSquare(int num) {
89114
long left = 1, right = num;
90-
while (left < right) {
91-
int mid = left + ((right - left) >> 1);
92-
if (num / mid <= mid) {
93-
right = mid;
94-
} else {
95-
left = mid + 1;
96-
}
115+
while (left < right)
116+
{
117+
long mid = left + right >> 1;
118+
if (mid * mid >= num) right = mid;
119+
else left = mid + 1;
97120
}
98121
return left * left == num;
99122
}
100123
};
101124
```
102125
126+
```cpp
127+
class Solution {
128+
public:
129+
bool isPerfectSquare(int num) {
130+
for (int i = 1; num > 0; i += 2) num -= i;
131+
return num == 0;
132+
}
133+
};
134+
```
135+
103136
### **Go**
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105138
```go
106139
func isPerfectSquare(num int) bool {
107140
left, right := 1, num
108141
for left < right {
109-
mid := left + (right-left)>>1
110-
if num/mid <= mid {
142+
mid := (left + right) >> 1
143+
if mid*mid >= num {
111144
right = mid
112145
} else {
113146
left = mid + 1
@@ -117,6 +150,15 @@ func isPerfectSquare(num int) bool {
117150
}
118151
```
119152

153+
```go
154+
func isPerfectSquare(num int) bool {
155+
for i := 1; num > 0; i += 2 {
156+
num -= i
157+
}
158+
return num == 0
159+
}
160+
```
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120162
### **...**
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122164
```

‎solution/0300-0399/0367.Valid Perfect Square/README_EN.md‎

Lines changed: 52 additions & 14 deletions
Original file line numberDiff line numberDiff line change
@@ -34,23 +34,33 @@ class Solution:
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def isPerfectSquare(self, num: int) -> bool:
3535
left, right = 1, num
3636
while left < right:
37-
mid = left + ((right- left) >> 1)
38-
if num // mid <= mid:
37+
mid = (left + right) >> 1
38+
if mid * mid >= num:
3939
right = mid
4040
else:
4141
left = mid + 1
4242
return left * left == num
4343
```
4444

45+
```python
46+
class Solution:
47+
def isPerfectSquare(self, num: int) -> bool:
48+
i = 1
49+
while num > 0:
50+
num -= i
51+
i += 2
52+
return num == 0
53+
```
54+
4555
### **Java**
4656

4757
```java
4858
class Solution {
4959
public boolean isPerfectSquare(int num) {
50-
int left = 1, right = num;
60+
long left = 1, right = num;
5161
while (left < right) {
52-
int mid = (left + right) >>> 1;
53-
if (num / mid <= mid) {
62+
long mid = (left + right) >>> 1;
63+
if (mid * mid >= num) {
5464
right = mid;
5565
} else {
5666
left = mid + 1;
@@ -61,34 +71,53 @@ class Solution {
6171
}
6272
```
6373

74+
```java
75+
class Solution {
76+
public boolean isPerfectSquare(int num) {
77+
for (int i = 1; num > 0; i += 2) {
78+
num -= i;
79+
}
80+
return num == 0;
81+
}
82+
}
83+
```
84+
6485
### **C++**
6586

6687
```cpp
6788
class Solution {
6889
public:
6990
bool isPerfectSquare(int num) {
7091
long left = 1, right = num;
71-
while (left < right) {
72-
int mid = left + ((right - left) >> 1);
73-
if (num / mid <= mid) {
74-
right = mid;
75-
} else {
76-
left = mid + 1;
77-
}
92+
while (left < right)
93+
{
94+
long mid = left + right >> 1;
95+
if (mid * mid >= num) right = mid;
96+
else left = mid + 1;
7897
}
7998
return left * left == num;
8099
}
81100
};
82101
```
83102
103+
```cpp
104+
class Solution {
105+
public:
106+
bool isPerfectSquare(int num) {
107+
for (int i = 1; num > 0; i += 2) num -= i;
108+
return num == 0;
109+
}
110+
};
111+
```
112+
84113
### **Go**
85114

86115
```go
87116
func isPerfectSquare(num int) bool {
88117
left, right := 1, num
89118
for left < right {
90-
mid := left + (right-left)>>1
91-
if num/mid <= mid {
119+
mid := (left + right) >> 1
120+
if mid*mid >= num {
92121
right = mid
93122
} else {
94123
left = mid + 1
@@ -98,6 +127,15 @@ func isPerfectSquare(num int) bool {
98127
}
99128
```
100129

130+
```go
131+
func isPerfectSquare(num int) bool {
132+
for i := 1; num > 0; i += 2 {
133+
num -= i
134+
}
135+
return num == 0
136+
}
137+
```
138+
101139
### **...**
102140

103141
```

‎solution/0300-0399/0367.Valid Perfect Square/Solution.cpp‎

Lines changed: 5 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -2,13 +2,11 @@ class Solution {
22
public:
33
bool isPerfectSquare(int num) {
44
long left = 1, right = num;
5-
while (left < right) {
6-
int mid = left + ((right - left) >> 1);
7-
if (num / mid <= mid) {
8-
right = mid;
9-
} else {
10-
left = mid + 1;
11-
}
5+
while (left < right)
6+
{
7+
long mid = left + right >> 1;
8+
if (mid * mid >= num) right = mid;
9+
else left = mid + 1;
1210
}
1311
return left * left == num;
1412
}

‎solution/0300-0399/0367.Valid Perfect Square/Solution.go‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,8 @@
11
func isPerfectSquare(num int) bool {
22
left, right := 1, num
33
for left < right {
4-
mid := left + (right-left)>>1
5-
if num/mid<=mid {
4+
mid := (left + right) >>1
5+
if mid*mid>=num {
66
right = mid
77
} else {
88
left = mid + 1

‎solution/0300-0399/0367.Valid Perfect Square/Solution.java‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1,9 +1,9 @@
11
class Solution {
22
public boolean isPerfectSquare(int num) {
3-
int left = 1, right = num;
3+
long left = 1, right = num;
44
while (left < right) {
5-
int mid = (left + right) >>> 1;
6-
if (num / mid <= mid) {
5+
long mid = (left + right) >>> 1;
6+
if (mid * mid >= num) {
77
right = mid;
88
} else {
99
left = mid + 1;

‎solution/0300-0399/0367.Valid Perfect Square/Solution.py‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -2,8 +2,8 @@ class Solution:
22
def isPerfectSquare(self, num: int) -> bool:
33
left, right = 1, num
44
while left < right:
5-
mid = left + ((right-left) >> 1)
6-
if num// mid <=mid:
5+
mid = (left + right) >> 1
6+
if mid* mid >=num:
77
right = mid
88
else:
99
left = mid + 1

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