[704] Binary Search

奇怪，怎麼可能沒寫過binary search ?!

重點在於要不要加等於XD（苦笑）

int search(int* nums, int numsSize, int target){

int left=0,right=numsSize-1;

int mid=(left+right)/2;

while (left<=right)

{

mid=(left+right)/2;

if (nums[mid] < target)

left=mid+1;

else if (nums[mid]> target)

right=mid -1;

else

return mid;

}

return -1;

}

[20251011]

這個更.... mid 竟然會算錯, l跟r 也亂亂的，天啊

int search(int* nums, int numsSize, int target) {

int l=0;

int r= numsSize-1;

int mid;

while (l<=r)

{

mid = l+(r-l)/2;

if (nums[mid]==target)

return mid;

if (nums[mid]>target)

r=mid-1;

if (nums[mid]<target)

l=mid+1;

}

return -1;

}

[20260913] 更新

先看一次再清掉重寫果然寫的比較快XD 而等號還是一樣漏掉了QQ

int search(int* nums, int numsSize, int target) {

int l=0;

int r= numsSize -1;

while (l<=r){

int mid = l+(r-l)/2;

if (nums[mid] == target)

return mid;

else if (nums[mid] < target)

l=mid+1;

else //if (nums[mid] > target)

r=mid-1;

}

return -1;

}