leetcode刷題記錄

我覺得每天來兩道，練習練習，再看看人家是怎麼優化的。

1.給定乙個整數陣列 nums 和乙個目標值 target，請你在該陣列中找出和為目標值的那 兩個 整數，並返回他們的陣列下標。

c++：暴力求解，204ms，9.1m

class solution 

for index, num in enumerate(nums):
another_num = target - num
if(another_num in map):
return [map[another_num], index]
map[num] = index
return none

c++: 32ms 10.5mb

/**

* definition for singly-linked list.
* struct listnode 
* };
*/class solution 
if(l2 != null)
sum = n1 + n2 + flag;
flag = sum / 10;
listnode* sub1 = new listnode(sum % 10);
sub->next = sub1;
sub = sub1;
}return out->next;
}};

# definition for singly-linked list.

# class listnode:
#     def __init__(self, x):
#         self.val = x
#         self.next = none
class solution:
def addtwonumbers(self, l1: listnode, l2: listnode) -> listnode:
out = listnode(0)
sub = out
flag = 0;
while(l1 != none or l2 != none):
x = l1.val if l1 else 0
y = l2.val if l2 else 0
sum = x + y + flag
flag = sum // 10
sub.next = listnode(sum%10)
sub = sub.next
if(l1 != none): l1 = l1.next
if(l2 != none): l2 = l2.next
if flag>0:
sub.next = listnode(1)
return out.next

c++: 4ms 9.1mb

class solution 

}cout << max << endl;
return max;
}};

class solution:

def lengthoflongestsubstring(self, s: str) -> int:
i,maxlength = 0,0
str = {}
for j in range(len(s)):
if( s[j] in str):
i = max(str[s[j]], i)
maxlength = max(maxlength, j-i+1)
str[s[j]] = j+1;
return maxlength

class solution:

def lengthoflongestsubstring(self, s: str) -> int:
max_length = 0
i = 0
test = ''
for j in s:
if j not in test:
test += j
i += 1
else:
if i >= max_length:
max_length = i
index = test.index(j)
test = test[(index+1):] + j
i = len(test)
if i > max_length:
max_length = i
return max_length

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