Compute the sum number in PIC() clause of COBOL

//***********************************************************************
//* This program is used to compute the sum value in the PIC clause.    *
//* It select the numbers in parenthesis, e.g. (02), and put 02 in dig  *
//* array in order. The var len is the digtal numbers, as above, it is  *
//* 2. And then use len to search the the number in comp_Num[] which    *
//* will be used to get the compensation of len. As above, it will get  *
//* 3. And now use 3-2 to get the weigh in weigh array.                 *
//* In the main function, it scan dig[] in order and scan weigh[] in a  *
//* contrary order.                                                     *
//***********************************************************************
#include <stdio.h>

static int weigh[5] = {0,1,10,100,1000};
static int comp_Num[5] = {1,2,3,4,5};
int getWeigh(int index);

void main(int args, char** argb)
{
	int sum = 0;
	int ch1 = 0;
	int ch2 = 0;
	int len = 0;
	int comp_Max = 0;
	int dig[4] = {0};
	FILE* fp = fopen(argb[1],"r");
	while(EOF != (ch1 = fgetc(fp))){
		if(ch1 == '('){
			while(EOF != (ch2 = fgetc(fp)) && ch2 != ')' ){
				dig[len++] = ch2 - 48;
			}
			comp_Max = comp_Num[len];
			while(len > 0){
				sum += dig[len-1] * getWeigh(comp_Max-len);
				len--;
			}
			len = 0;
		}
	}
	printf("sum= %d \n", sum);
	if(fp != NULL){
		fclose(fp);
	}
}


int getWeigh(int index)
{
	return weigh[index];
}