P6982 [NEERC2015]Jump 题意 给你一个未知的 01 串,每次可以输出询问一个 01 串,如果该串中正确的个数刚好等于 \(n\) 或者 \(n/2\) ,将会返回相应的答案,否则会返回 0 .求出这个串.(询问次数不大于 \(n+500\) ) 思路 先无视询问次数,我们来想一下确定性算法怎么做. 第一步,我们来试着找出 \(n/2\) 正确的串. 首先,我们设一个全 0​ 串,每次修改最左边的 0 为 1,在这至多 \(n\) 次询问中,我们一定能找到一个有 \(n/2\)…

A frog is crossing a river. The river is divided into x units and at each unit there may or may not exist a stone. The frog can jump on a stone, but it must not jump into the water. Given a list of stones' positions (in units) in sorted ascending ord…

Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Determine if you are able to reach the last index. For example:A = …

Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Your goal is to reach the last index in the minimum number of jumps…

Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Your goal is to reach the last index in the minimum number of jumps…

我一开始认为这是一道DP的题目.其实,可以维护一个maxReach,并对每个元素更新这个maxReach = max(maxReach, i + nums[i]).注意如果 i>maxReach,说明从起点开始能跳到的最远距离不到i, 所以i后面的点也就无法到达了.另外如果 maxReach >= n-1 说明已经可以跳到终点了,之后的点也就不用继续检查了. class Solution(object): def canJump(self, nums): """…

题目: Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Your goal is to reach the last index in the minimum number of j…

Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Your goal is to reach the last index in the minimum number of jumps…

Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Determine if you are able to reach the last index. For example:A = …

gdb或者vlagrind报告: ==14569== Jump to the invalid address stated on the next line ==14569== at 0x0: ??? ==14569== Address 0x0 is not stack'd, malloc'd or (recently) free'd 错误原因:函数通过jmp,call,ret等指令跳转到0x00,错误可能出现的范围 1.函数缓冲区溢出覆盖了返回地址,然后又调用了return,例如 #inclu…