Leetcode:Minimum Path Sum

Given a m x n grid filled with non-negative numbers, find a path from top left to bottom right which minimizes the sum of all numbers along its path.

Note: You can only move either down or right at any point in time.

利用动态规划,对于点[i,j]来说,dp[i][j] = min(dp[i-1][j],dp[i][j-1])+grid;初始化边界值,不断的迭代就可以获得最终解。

int minPath(vector<vector<int> >& grid){
    int column = grid[0].size();
    int row = grid.size();
    int** dp = new int*[row];
    for(int i=0;i<row;i++){
        dp[i] = new int[column];
    }
    for(int i=0;i<row;i++)
        for(int j=0;j<column;j++)
            dp[i][j] = 0;
    dp[0][0] = grid[0][0];
    for(int j=1;j<column;++j)//初始化边界
        dp[0][j] = dp[0][j-1]+grid[0][j];
    for(int i=1;i<row;++i)
        dp[i][0] = dp[i-1][0]+grid[i][0];
    for(int i=1;i<row;++i)
        for(int j=1;j<column;++j)
            dp[i][j] = min(dp[i-1][j],dp[i][j-1])+grid[i][j];
    int result = dp[row-1][column-1];
    for(int j=0;j<row;j++)
        delete[] dp[j];
    delete[] dp;
    return result;
}
int main(){
    //int mp = 5;
    vector<vector<int> > mp;
    vector<int> temp;
    for(int i=0;i<4;++i){
        for(int j=0;j<5;++j){
            int ss = rand()%8;
            cout<<ss<<" ";
            temp.push_back(ss);
        }
        cout<<endl;
        mp.push_back(temp);
        temp.clear();
    }
    int num_pow = minPath(mp);
    cout<<num_pow<<endl;
}
原文地址:https://www.cnblogs.com/zhang-wen/p/4797047.html