贪心算法-demo1

class Solution {
    public int findContentChildren(int[] g, int[] s) {
        Arrays.sort(g);
        Arrays.sort(s);
        int index_g = 0;
        int index_s = 0;
        while(index_g
            if(g[index_g]<=s[index_s]){
                index_g++;
                index_s++;
            }else{
                index_s++;
            }
        }
        return index_g;
    }
}

class Solution {
    public int wiggleMaxLength(int[] nums) {
        if(nums.length==1){
            return 1;
        }
        //统计峰值
        int res = 1;
        int pre = 0;
        int cur = 0;
        for(int i=0;i
            cur = nums[i+1] - nums[i];
            if((cur>0&&pre<=0)||(cur<0&&pre>=0)){
                res++;
                pre = cur;
            }
        }
        return res;
    }
}

class Solution {
    public int maxSubArray(int[] nums) {
        int count = 0;
        //初试化最小负数
        int res = Integer.MIN_VALUE;;
        for(int i=0;i
            count+=nums[i];
            if(res
                res = count;
            }
            if(count<0){
                count = 0;
            }
        }
        return res;
    }
}

class Solution {
    public int maxProfit(int[] prices) {
        int res = 0;
        for(int i=0;i
            int temp = prices[i+1]-prices[i];
            if(temp>0){
                res+=temp;
            }
        }
        return res;
    }
}

class Solution {
    public boolean canJump(int[] nums) {
    //转换为最大覆盖范围，不关心当前位置跳多少步
        int cover = 0;
        if(nums.length==1){
            return true;
        }
        for(int i=0;i<=cover;i++){
            cover = Math.max(i+nums[i],cover);
            if(cover>=nums.length-1){
                return true;
            }
        }
        return false;
    }
}