Nested loop comparison in Python,Java and C -

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the following code in python takes long run. (i couldn't wait until program ended, though friend told me him took 20 minutes.)

but equivalent code in java runs in approximately 8 seconds , in c takes 45 seconds.

i expected python slow not much, , in case of c expected faster java slower. jvm using loop unrolling technique achieve speed? there reason python being slow?

import time st=time.time() in xrange(0,100000):     j in xrange(0,100000):         continue; print "time taken : ",time.time()-st

gcc 4.2 -o1 flag or higher optimize away loop , program takes 1 milli second execute. benchmark not representative far real world use. you're doing nested loop reason, , never leave empty. python doesn't optimize away loop, although see no technical reason why couldn't.

python slower c because it's further machine language. xrange nice abstraction adds heavy layer of machine code compared simple c loop.

c source:

int main( void ){         int i, j;         (i=0;i<100000;i++){                 (j=0;j<100000;j++){                         continue;                 }         }         return 0; }

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