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class Solution {
public:
    int minDistance(string word1, string word2) {
        len1 = word1.length();
        len2 = word2.length();
        initdptable();
        for(int i = 1;i <= len1;i++) {
            for(int j = 1;j <= len2;j++) {
                dpTable[i][j] = getMin(word1[i-1] == word2[j-1] ? dpTable[i-1][j-1]:dpTable[i-1][j-1] + 1,dpTable[i-1][j]+1,dpTable[i][j-1]+1);
            }
        }
        //displaydptable();
        return dpTable[len1][len2];
    }
private:
    int **dpTable;
    int len1,len2;
    int getMin(int a,int b,int c) {
        int min = a;
        if(min > b)min = b;
        if(min > c)min = c;
        return min;
    }
    void initdptable() {
        dpTable = new int *[len1+1];
        for(int i = 0;i <= len1;i++) {
            dpTable[i] = new int[len2+1];
        }
        for(int i = 0;i <= len1;i++) {
            dpTable[i][0] = i;
        }
        for(int i = 0;i <= len2;i++) {
            dpTable[0][i] = i;
        }
    }
    void displaydptable() {
        for(int i = 0;i <= len1;i++) {
            for(int j = 0;j <= len2;j++) {
                cout << dpTable[i][j] << " ";
            }
            cout << endl;
        }
    }
};