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Yellow.Flash's blog

Help in a DP problem (google kickstart 2017)
By Yellow.Flash, history, 7 years ago, In English

problem B google kickstart

Someone please explain the approach for this problem.

Thanks

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7 years ago, # |
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Auto comment: topic has been updated by Yellow.Flash (previous revision, new revision, compare).

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7 years ago, # |
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calc dp[i][j] -> is there a string, that suitable prefix i of the first template and the prefix j of the second pattern?

and then easy transitions:


dp[0][0] = true; 

if (a[i] != '*' && b[j] != '*' && a[i] == b[j])
{
    dp[i + 1][j + 1] |= dp[i][j];
}

if (a[i] == '*')
{
    dp[i + 1][j] |= dp[i][j];
    dp[i + 1][j + 1] |= dp[i][j];
}

if (b[j] == '*')
{
    dp[i][j + 1] |= dp[i][j];
    dp[i + 1][j + 1] |= dp[i][j];
}

answer in dp[n][m]

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    7 years ago, # ^ |
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    How you are using this information : A star can match between zero and four letters ?

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      7 years ago, # ^ |
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      oh, sorry, i misread this. you can copy one star 4 times :)

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