class Solution {
public:
int uniquePaths(int m, int n) {
vector<vector<int>> dp(m, vector<int>(n));
for (int i = 0; i < dp.size(); i++) dp[i][0] = 1;
for (int j = 0; j < dp[0].size(); j++) dp[0][j] = 1;
for (int i = 1; i < dp.size(); i++){
for (int j = 1; j < dp[0].size(); j++){
dp[i][j] = dp[i][j- 1] + dp[i - 1][j];
}
}
return dp[dp.size() - 1][dp[0].size() - 1];
}
};
文章链接:代码随想录
题目链接:63. 不同路径 II
dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
这句多打了个等号导致一直过不了,注意注意!
class Solution {
public:
int uniquePathsWithObstacles(vector<vector<int>>& obstacleGrid) {
int m = obstacleGrid.size();
int n = obstacleGrid[0].size();
vector<vector<int>> dp(m, vector<int>(n, 0));
for (int i = 0; i < m && obstacleGrid[i][0] == 0; i++) dp[i][0] = 1;
for (int j = 0; j < n && obstacleGrid[0][j] == 0; j++) dp[0][j] = 1;
for (int i = 1; i < m; i++){
for (int j = 1; j < n; j++){
if (obstacleGrid[i][j] == 1) continue;
dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
}
}
/*
for (int i = 0; i < m; i++){
for (int j = 0; j < n; j++){
cout << dp[i][j] << endl;
}
}
*/
return dp[m - 1][n - 1];
}
};
第三十九天打卡,加油!!!