第22天--算法（Leetcode 53,62）
53.最大子数组和
public int maxSubArray(int[] nums) { int res = Integer.MIN_VALUE; int curRes = 0; if(nums == null || nums.length == 0) { return 0; } for(int i = 0;i < nums.length;i ++) { curRes += nums[i]; res = Math.max(curRes,res); curRes = curRes < 0 ? 0 : curRes; } return res; }62.不同路径
public int uniquePaths(int m, int n) { int x = m + n - 2; int y = n - 1; long o1 = 1; long o2 = 1; for(int i = m,j = 1;i <= x && j <= n - 1;i ++,j ++) { o1 *= i; o2 *= j; long temp = gcd(o1,o2); o1 /= temp; o2 /= temp; } return (int)o1; } public long gcd(long x,long y) { return y == 0 ? x : gcd(y,x % y); }