leetcode

Dynamic Programming I: Day 16

3 files changed, 45 insertions(+), 0 deletions(-)

diff --git a/ Problems/0064.cpp b/ Problems/0064.cpp

@@ -0,0 +1,25 @@

class Solution {

public:

int minPathSum(vector<vector<int>> &grid) {

int n = grid.size(), m = grid[0].size();

vector<vector<int>> mat(n, vector<int>(m, INT_MAX));

queue<pair<int, int>> q;

q.push({0, 0}), mat[0][0] = 0;

while (!q.empty()) {

auto [x, y] = q.front();

q.pop();

mat[x][y] += grid[x][y];

if (x + 1 < n) {

if (mat[x + 1][y] == INT_MAX) q.push({x + 1, y});

mat[x + 1][y] = min(mat[x + 1][y], mat[x][y]);

}

if (y + 1 < m) {

if (mat[x][y + 1] == INT_MAX) q.push({x, y + 1});

mat[x][y + 1] = min(mat[x][y + 1], mat[x][y]);

}

}

return mat.back().back();

}

};

diff --git a/ Problems/0221.cpp b/ Problems/0221.cpp

@@ -0,0 +1,18 @@

class Solution {

public:

int maximalSquare(vector<vector<char>> &matrix) {

int n = matrix.size(), m = matrix[0].size(), res = 0;

vector<vector<int>> dp(n, vector<int>(m, 0));

for (int i = 0; i < n; i++) {

for (int j = 0; j < m; j++) {

if (!i || !j || matrix[i][j] == '0') {

dp[i][j] = matrix[i][j] - '0';

} else {

dp[i][j] = min(dp[i - 1][j - 1], min(dp[i - 1][j], dp[i][j - 1])) + 1;

}

res = max(res, dp[i][j]);

}

}

return res * res;

}

};

diff --git a/ README.md b/ README.md

@@ -60,6 +60,7 @@ for solving problems. | 0061 | Medium | [Rotate List](Problems/0061.cpp) | | 0062 | Medium | [Unique Paths](Problems/0062.cpp) | | 0063 | Medium | [Unique Paths II](Problems/0063.cpp) |

| 0064 | Medium | [Minimum Path Sum](Problems/0064.cpp) |

| 0066 | Easy | [Plus One](Problems/0066.cpp) | | 0067 | Easy | [Add Binary](Problems/0067.cpp) | | 0070 | Easy | [Climbing Stairs](Problems/0070.cpp) |

@@ -142,6 +143,7 @@ for solving problems. | 0210 | Medium | [Course Schedule II](Problems/0210.cpp) | | 0213 | Medium | [House Robber II](Problems/0213.cpp) | | 0217 | Easy | [Contains Duplicate](Problems/0217.cpp) |

| 0221 | Medium | [Maximal Square](Problems/0221.cpp) |

| 0222 | Medium | [Count Complete Tree Nodes](Problems/0222.cpp) | | 0223 | Medium | [Rectangle Area](Problems/0223.cpp) | | 0226 | Easy | [Invert Binary Tree](Problems/0226.cpp) |