在循环中计算功率时值错误

Question

I have problem in calculating a power of an integer in a C language.

I have to convert an array value to an equivalent integer ie {5,3,0,5,3} to 53053

I have the following code

int repsEqual(int a[], int len, int n)
{
    int temp = 0;
    int i = 0;

    for(i; i < len;i++)
    {
        temp =   temp + a[i] * pow(10, (len - (i+1)));
    }

   if(temp == n) {
       return 1;
   }
   else {
       return 0;
   }
}

It always return 0. Since the power is wrongly outputted. {5,3,0,5,3} returns 53052.

Please help me guys

Answer 1

You are mixing floating point and integer arithmetic and suffering from rounding problems as a result. There is no need to call pow , which is a floating point library function, and overkill for this assignment. A simpler implementation using just integer arithmetic would be:

int repsEqual(int a[], int len, int n)
{
    int temp = 0;

    for (int i = 0; i < len; i++)
    {
        temp = temp * 10 + a[i];
    }

    return (temp == n);
}

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