39 lines
1.3 KiB
C++
39 lines
1.3 KiB
C++
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// Source : https://leetcode.com/problems/ransom-note/
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// Author : Hao Chen
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// Date : 2016-08-24
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/***************************************************************************************
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*
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*
Given
an
arbitrary
ransom
note
string
and
another
string
containing
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*
letters from
all
the
magazines,
write
a
function
that
will
return
true
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*
if
the
ransom
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* note
can
be
constructed
from
the
magazines ;
otherwise,
it
will
return
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*
false.
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*
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* Each
letter
in
the
magazine
string
can
only
be
used
once
in
your
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*
ransom
note.
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*
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* Note:
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* You may assume that both strings contain only lowercase letters.
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*
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* canConstruct("a", "b") -> false
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* canConstruct("aa", "ab") -> false
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* canConstruct("aa", "aab") -> true
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***************************************************************************************/
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class Solution {
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public:
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bool canConstruct(string ransomNote, string magazine) {
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unordered_map<char, int> m;
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for(int i=0; i<magazine.size(); i++) {
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m[magazine[i]]++;
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}
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for (int i=0; i<ransomNote.size(); i++) {
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char c = ransomNote[i];
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if (m[c] <=0 ) return false;
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m[c]--;
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}
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return true;
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}
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};
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