第一次作业
买卖股票的最佳时机 #include "stdafx.h" #include<iostream> using namespace std;
int _tmain(int argc, _TCHAR* argv[]) { int a[]={3,2,3,1,2}; int i,j,k=0; for(i=0;i<5;i++) { for(j=i;j<5-i;j++) { if(a[j]-a[i]>k) k=a[j]-a[i]; } } cout<<k; return 0; }
爬楼梯
class Solution {
public:
/** * @param n: An integer * @return: An integer */
long climbStairs(int n) {
// write your code here if(n==0) return 1; long s = 1; int i=1; int j=n-i; while(i<=j){ s=s+(getCni(j,i)+0.1); i++; j=n-i; } return s; } long getCni( long n, long i){ long s = 1; for (int j = 0; j<i; j++ ){ s = s*( n - j )/(j+1); } return s ; } };
删除排序数组中的重复数字 class Solution { public: /** * @param A: a list of integers * @return : return an integer */ int removeDuplicates(vector<int> &nums) { // write your code here if(nums.empty()) { return 0; }//if int n = nums.size(),k=0; for(int i=1;i<n;++i) { if(nums[i] != nums[k]) { nums[++k] = nums[i]; }//if }//for nums.resize(k+1); return k+1; } };