equal [C++ Reference]
Keywords: stl,algorithm,equal
Date: 2009-10-09T00:59:03-0700

[[equal]]
C++ Reference
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## equal

Syntax:

        #include <algorithm>
        bool equal( input_iterator start1, input_iterator end1, input_iterator2 start2 );
        bool equal( input_iterator start1, input_iterator end1, input_iterator2 start2, BinPred p );

The equal() function returns true if the elements in two ranges are the same. The first range of elements are those between start1 and end1. The second range of elements has the same size as the first range but starts at start2.

If the binary predicate p is specified, then it is used instead of == to compare each pair of elements.

For example, the following code uses equal() to compare two vectors of integers:

       vector<int> v1;
       for( int i = 0; i < 10; i++ ) {
         v1.push_back( i );
       }

       vector<int> v2;
       for( int i = 0; i < 10; i++ ) {
         v2.push_back( i );
       }

       if( equal( v1.begin(), v1.end(), v2.begin() ) ) {
         cout << "v1 and v2 are equal" << endl;
       } else {
         cout << "v1 and v2 are NOT equal" << endl;
       }

Related Topics: find_if, lexicographical_compare, mismatch, search

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