c - Why does this program gives no output for float and double datatypes? -

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why program gives no output float , double datatypes. however, result when same code replaced loop??

      # include <stdio.h>        int main()       {        float x=1.1;                            while (x==1.1)        {           printf("%f\n",x);         x=x-0.1;        }        return 0;       } 

   float x=1.1;                        while (x==1.1)

float , double variables not capable of storing exact value of 1.1, close approximation. exact value in float , double different due difference in precision.

1.1 double value. storing 1.1 double float alter value. compare double value 1.1 not quite equal , never enter condition.

for work need write 1.1f ensure working same data type everywhere. in addition i'm sure else explain why comparing floating point values exact equality bad idea.


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