AcWing 56. y总代码:从1到n整数中1出现的次数
原题链接
困难
作者:
杨大鑫_ωノ
,
2021-05-21 11:48:46
,
所有人可见
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阅读 513
class Solution {
public:
int numberOf1Between1AndN_Solution(int n) {
if(!n) return 0;
vector<int> number;
while(n) number.push_back(n % 10) , n /= 10;
int res = 0;
for(int i = number.size() - 1; i >= 0; i--)
{
auto left = 0, right = 0, t = 1;
for(int j = number.size() - 1; j > i; j--) left = left * 10 + number[j];
for(int j = i - 1; j >= 0; j--) right = right * 10 + number[j], t *= 10;
res += left * t;
if(number[i] == 1) res += right + 1;
else if(number[i] > 1) res += t;
}
return res;
}
};