error:
use dp equation:
dp[i][j]: whether string s of first i characters is match with
string p of first j characters
initial:
dp[0][0] = true;
dp[0][j] = dp[0][j - 1] (if p[j - 1] == '*')
transform equation:
dp[i][j] = dp[i - 1][j - 1] (if s[i - 1] == p[j - 1] || p[j - 1] == '?')
dp[i][j] = dp[i][j - 1] || dp[i - 1][j] (if p[j - 1] == '*')Why dp[i][j] = dp[i][j - 1] || dp[i - 1][j] (if p[j - 1] == ‘*’) ?
If * is not used, or treat it as empty character, so the
dp[i][j] if depends on dp[i][j - 1]
if * is used, we treat the whole string p[0…j - 1] as a entity, and see if p[0…j - 1] is match s[0…i - 2] or not, if match, since * can match any character append of
s[0…i - 2], i.e., s[i - 1]. So we can match it. Perform same inference if p[0…j - 1] is mismatch with s[0…i - 2]
