119. Pascal's Triangle II

class Solution:
    def getRow(self, rowIndex: int) -> List[int]:
        f = [1] * (rowIndex + 1)
        for i in range(2, rowIndex + 1):
            for j in range(i - 1, 0, -1):
                f[j] += f[j - 1]
        return f

class Solution {
    public List<Integer> getRow(int rowIndex) {
        List<Integer> f = new ArrayList<>();
        for (int i = 0; i < rowIndex + 1; ++i) {
            f.add(1);
        }
        for (int i = 2; i < rowIndex + 1; ++i) {
            for (int j = i - 1; j > 0; --j) {
                f.set(j, f.get(j) + f.get(j - 1));
            }
        }
        return f;
    }
}

class Solution {
public:
    vector<int> getRow(int rowIndex) {
        vector<int> f(rowIndex + 1, 1);
        for (int i = 2; i < rowIndex + 1; ++i) {
            for (int j = i - 1; j; --j) {
                f[j] += f[j - 1];
            }
        }
        return f;
    }
};

func getRow(rowIndex int) []int {
	f := make([]int, rowIndex+1)
	for i := range f {
		f[i] = 1
	}
	for i := 2; i < rowIndex+1; i++ {
		for j := i - 1; j > 0; j-- {
			f[j] += f[j-1]
		}
	}
	return f
}

function getRow(rowIndex: number): number[] {
    const f: number[] = Array(rowIndex + 1).fill(1);
    for (let i = 2; i < rowIndex + 1; ++i) {
        for (let j = i - 1; j; --j) {
            f[j] += f[j - 1];
        }
    }
    return f;
}

impl Solution {
    pub fn get_row(row_index: i32) -> Vec<i32> {
        let n = (row_index + 1) as usize;
        let mut f = vec![1; n];
        for i in 2..n {
            for j in (1..i).rev() {
                f[j] += f[j - 1];
            }
        }
        f
    }
}