var minDistance = function(word1, word2) {
let n = word1.length;
let m = word2.length;
if(n*m === 0) return n+m;
if(word1 === word2) return 0;
let dp = [];
for(let i = 0;i <= n;i++){
dp.push([])
for(let j = 0;j <= m;j++){
if(i*j){
dp[i][j] = word1[i-1] == word2[j-1]? dp[i-1][j-1]: (Math.min(dp[i-1][j],dp[i][j-1],dp[i-1][j-1]) + 1);
}else{
dp[i][j] = i + j;
}
}
}
return dp[n][m];
};
while(str1 = readline()) {
const str2 = readline();
console.log(minDistance(str1, str2));
}