34 lines
505 B
C
34 lines
505 B
C
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#define MAX 1000000-1
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#include <stdio.h>
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#include <math.h>
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int main( )
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{
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unsigned int max_steps = 0;
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unsigned int max_start;
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unsigned int test;
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unsigned long ctest;
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unsigned int steps;
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for(test = MAX; test > 1 ; test--)
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{
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ctest = test;
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steps = 1;
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while(ctest != 1)
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{
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ctest = ( ctest % 2 ) ? ctest * 3 + 1 : ctest / 2;
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steps++;
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}
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if(steps > max_steps)
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{
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max_start = test;
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max_steps = steps;
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}
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}
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printf( "%lu", max_start );
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}
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