最小编辑距离

/**
 * @param {string} word1
 * @param {string} word2
 * @return {number}
 */
var minDistance = function(word1, word2) {
        let temp = new Array();
    let n = word1.length;
    let m = word2.length;
    if(n==0||m==0){
        return n>m? n:m;
    }
   
    for(let i=0;i<=n;i++){
        let demo = new Array();
        for(let j=0;j<=m;j++){
            demo[j] = 0;
        }
        temp.push(demo);
    }

    for(let i = 1;i<=n;i++){
        temp[i][0] = i;
    }
    for(let j=1;j<=m;j++){
        temp[0][j] = j;
    }

    for(let i=1;i<=n;i++){
        for(let j=1;j<=m;j++){
            if(word1[i-1]== word2[j-1]){
                temp[i][j] = temp[i-1][j-1];
            }else{
                temp[i][j] = Math.min(
                    temp[i][j-1]+1,
                    temp[i-1][j]+1,
                    temp[i-1][j-1]+1
                )
            }
        }
    }
    return temp[n][m];
};