《LeetCode零基础指南》(第七讲) 贪心

• • 1913. 两个数对之间的最大乘积差
  • 976. 三角形的最大周长
  • 561. 数组拆分 I
  • 881. 救生艇
  • 324. 摆动排序 II
  • 455. 分发饼干
  • 1827. 最少操作使数组递增

class Solution {
public:
    int maxProductDifference(vector& nums) {
        sort(nums.begin(),nums.end());
        return nums[nums.size()-1]*nums[nums.size()-2]-nums[1]*nums[0];
    }
};

class Solution {
public:
    static bool cmp(int a,int b) {
        return a>b;
    }
    int largestPerimeter(vector& nums) {
        int n=nums.size();
        sort(nums.begin(),nums.end(),cmp);
        for(int i=0;inums[i]) return nums[i]+nums[i+1]+nums[i+2];
        }
        return 0;
    }
};

class Solution {
public:
    int arrayPairSum(vector& nums) {
        int sum=0,n=nums.size();
        sort(nums.begin(),nums.end());
        for(int i=0;i 
881. 救生艇 
class Solution {
public:
    int numRescueBoats(vector& people, int limit) {
        int ans=0,n=people.size();
        sort(people.begin(),people.end());
        for(int i=n-1;i>=0;i--) {
            if(people[i]!=-1) {
                int l=0,r=i-1;
                while(l>1;
                    if(people[mid]<=limit-people[i]) l=mid;
                    else r=mid-1;
                }
                while(l>=0&&people[l]==-1) l--;
                cout<=0&&people[l]!=-1&&people[l]+people[i]<=limit) people[l]=-1;
                ans++;
            }
        }
        return ans;
    }
};
 
324. 摆动排序 II 
class Solution {
public:
    void wiggleSort(vector& nums) {
        vectorres=nums;
        sort(res.begin(),res.end());
        int n=nums.size(),j=n-1;
        for(int i=1;i 
455. 分发饼干 
const int N=3e4+10;
bool st[N];

class Solution {
public:
    int findContentChildren(vector& g, vector& s) {
        memset(st,false,sizeof(st));
        sort(s.begin(),s.end());
        int ans=0,n=g.size();
        for(int i=0;i>1;
                if(s[mid]>=g[i]) r=mid;
                else l=mid+1;
            }
            while(l=g[i]) st[l]=true,ans++; 
        }
        return ans;
    }
};
 
1827. 最少操作使数组递增 
class Solution {
public:
    int minOperations(vector& nums) {
        int ans=0;
        for(int i=1;i