Hard-题目23:45. Jump Game II

题目原文:
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.

For example:
Given array A = [2,3,1,1,4]

The minimum number of jumps to reach the last index is 2. (Jump 1 step from index 0 to 1, then 3 steps to the last index.)
题目大意:
给出一个正整数数组,你最开始站在数组的开头,每个元素代表你一次跳的最远距离,问你至少需要多少次才能跳到终点?
题目分析:
使用一个变量nextMax记录当前count次跳跃能到达的最远点,并使用count记录已经跳跃的次数。
从头开始遍历数组,设遍历到第i个元素,则当i+num[i]>nextMax时,说明count 次跳跃已经不够用了,则更新nextMax和count。
源码:(language:c)

int jump(int* nums, int numsSize) {
    int count = 0, max = 0,nextMax = 0;
    for (int i = 0 ; i <= max && i < numsSize - 1; i++) {
        nextMax = nextMax> i + nums[i]?nextMax:i+nums[i];
        if (i == max) {
            max = nextMax;
            count++;
        }
    }
    return count;
}

成绩:
7ms,beats 70.37%,8ms,59.26%

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