Mock Interview: Facebook #2
2699 ワード
Range Sum Query
class NumArray {
int[] nums;
public NumArray(int[] nums) {
this.nums = nums;
}
public int sumRange(int left, int right) {
int sum = 0;
for (int i = left; i <= right; i++) {
sum += this.nums[i];
}
return sum;
}
}
/**
* Your NumArray object will be instantiated and called as such:
* NumArray obj = new NumArray(nums);
* int param_1 = obj.sumRange(left,right);
*/
Runtime: 62 ms, faster than 22.42% of Java online submissions for Range Sum Query - Immutable.Memory Usage: 41.5 MB, less than 94.40% of Java online submissions for Range Sum Query - Immutable.
private int[] sum;
public NumArray(int[] nums) {
sum = new int[nums.length + 1];
for (int i = 0; i < nums.length; i++) {
sum[i + 1] = sum[i] + nums[i];
}
}
public int sumRange(int i, int j) {
return sum[j + 1] - sum[i];
}
caching~~~Read N Characters Given Read4
/**
* The read4 API is defined in the parent class Reader4.
* int read4(char[] buf4);
*/
public class Solution extends Reader4 {
/**
* @param buf Destination buffer
* @param n Number of characters to read
* @return The number of actual characters read
*/
public int read(char[] buf, int n) {
char[] four = new char[4];
int read = 0;
int copy = 0;
while (read < n && copy < n / 4) {
four = read4(four);
}
if (n >= buf.length) {
return buf.length;
} else {
return (int) n;
}
}
}
Wrong Answer問題が何なのか分からないが...
public class Solution extends Reader4 {
public int read(char[] buf, int n) {
int copiedChars = 0, readChars = 4;
char[] buf4 = new char[4];
while (copiedChars < n && readChars == 4) {
readChars = read4(buf4);
for (int i = 0; i < readChars; ++i) {
if (copiedChars == n)
return copiedChars;
buf[copiedChars] = buf4[i];
++copiedChars;
}
}
return copiedChars;
}
}
Runtime: 0 ms, faster than 100.00% of Java online submissions for Read N Characters Given Read4.Memory Usage: 36.6 MB, less than 97.22% of Java online submissions for Read N Characters Given Read4.
Reference
この問題について(Mock Interview: Facebook #2), 我々は、より多くの情報をここで見つけました https://velog.io/@jwade/Mock-Interview-Facebook-2テキストは自由に共有またはコピーできます。ただし、このドキュメントのURLは参考URLとして残しておいてください。
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