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// Program : eratosthenes.C
// Calculate prime numbers in {2 ,... ,999} using
// Eratosthenes ’ sieve .
# include < iostream >
int main ()
{
// definition and initialization : provides us with
// Booleans crossed_out [0] ,... , crossed_out [999]
bool crossed_out [1000];
for ( unsigned int i = 0; i < 1000; ++ i)
crossed_out[i ] = false ;
// computation and output
std :: cout < < " Prime numbers in {2 ,... ,999}:\ n";
for ( unsigned int i = 2; i < 1000; ++ i)
if (! crossed_out[i ]) {
// i is prime
std :: cout < < i < < " ";
// cross out all proper multiples of i
for ( unsigned int m = 2* i ; m < 1000; m += i)
crossed_out[ m ] = true ;
}
std :: cout < < "\ n";
}
return 0;
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Prec. Assoc.
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return 0;
delete [] crossed_out ;
n
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// Program : eratosthenes2.C
// Calculate prime numbers in {2 ,... ,n -1} using
// Eratosthenes ’ sieve .
# include < iostream >
int main ()
{
// input
std :: cout < < " Compute prime numbers in {2 ,... ,n -1} for n =? ";
unsigned int n;
std :: cin > > n;
// definition and initialization : provides us with
// Booleans crossed_out [0] ,... , crossed_out[n -1]
bool * crossed_out = new bool [ n ];
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for ( unsigned int i = 0; i < n ; ++ i)
crossed_out[i ] = false ;
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std :: cout < < " Prime numbers in {2 ,... ," < < n -1 < < " }:\ n ";
for ( unsigned int i = 2; i < n ; ++ i)
if (! crossed_out[i ]) {
// i is prime
std :: cout < < i < < " ";
// cross out all proper multiples of i
for ( unsigned int m = 2* i ; m < n ; m += i )
crossed_out[ m ] = true ;
}
std :: cout < < "\ n";
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# include < iostream >
int main ()
{
// search string
char s [] = " bool ";
int main ()
{
// definition and initialization : provides us with
// Booleans crossed_out [0] ,... , crossed_out [999]
bool
3
int[3]
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// Program : eratosthenes. C
// Calculate prime numbers in {2 ,... ,999} using
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// compare search string with window at j - th element
if ( w < m || s[j ] != t [( i+j )% m ])
// input text still too short , or mismatch :
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std :: cout < < t[i ];
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bool
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// cyclic text window of size m
char * t = new char [m ];
su
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unsigned int m = 0;
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return 0;
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if ( floor [r -1][ c ] == i -1 || floor [ r +1][ c ] == i -1 ||
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floor [r ][ c ] = -3; // mark cell as being on shortest path
// go to some neighbor with distance d
if
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else if ( floor [r ][ c -1] == d ) - - c;
else
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// print floor with shortest path
for ( int r =1; r <n +1; ++ r ) {
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if
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std :: cout
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int m ; std :: cin > > m ; // number of columns
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// main loop : find and label cells reachable in i =1 ,2 ,... steps
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if ( floor [r -1][ c ] == i -1 || floor [ r +1][ c ] == i -1 ||
floor [r ][c -1] == i -1 || floor [ r ][ c +1] == i -1 ) {
floor [r ][ c ] = i ; // label cell with i
progress = true ;
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// find the first occurrence of a string ( provided as command
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"string_matching2"
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{1 , 5 , 9} , // the three elements
{4 , 6 , 1} // the three elements
},
{ // the 2 elements of a [2]:
{5 , 9 , 0} , // the three elements
{1 , 5 , 3} // the three elements
},
{ // the 2 elements of a [3]:
{6 , 7 , 7} , // the three elements
{7 , 8 , 5} // the three elements
}
};
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0 x3c , 0 x54 , 0 x48 , 0 x00 ,
0 x04 , 0 x1c , 0 x00 , 0 x1c ,
0 x14 , 0 x08 , 0 x00 , 0 x1f ,
0 x00 , 0 x0a , 0 x15 , 0 x1f };
test_height
test_bits
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