[LeetCode] Pascal's Triangle
Given numRows, generate the first numRows of Pascal's 易做图.For example, given numRows = 5,
Return
[
[1],
[1,1],
[1,2,1],
[1,3,3,1],
[1,4,6,4,1]
]
问题描述：给定一个整数numRows，生成Pascal三角形的前numRows行。
将该三角形的左边对齐，就能够发现，tri[i][j] = tri[i-1][j-1] + tri[i-1][j]。
class Solution {
public:
vector<vector<int> > generate(int numRows) {
// Note: The Solution object is instantiated only once and is reused by each test case.
if(numRows == 0)
return vector<vector<int> >(0);
vector<vector<int> > ivec;
int i = 0, j = 0;
for(i = 0; i < numRows; i++) {
vector<int> vec;
for(j = 0; j < i+1; j++) {
if(j == 0 || j == i)
vec.push_back(1);
else
vec.push_back(ivec[i-1][j-1] + ivec[i-1][j]);
}
ivec.push_back(vec);
}
return ivec;
}
};
补充：软件开发 , C++ ,
