目录
题目
待添加
解法一
            
            
              cpp
              
              
            
          
          int numDistinct(char* s, char* t) {
    const int len1 = strlen(s), len2 = strlen(t);
    unsigned long long dp[len2 + 1];
    memset(dp, 0, sizeof(dp));
    dp[0] = 1;
    for (int i = 1; i <= len1; i++) {
        for (int j = len2; j >= 1; j--) {
            if (s[i - 1] == t[j - 1]) {
                dp[j] += dp[j - 1];
            }
        }
    }
    return dp[len2];
}