C :

#include <stdio.h>
#include <stdlib.h>
typedef struct node
{
	char symbol;
	int freq;
	int parent;
	int tag;
}NODE;

int main()
{
	NODE* tree;
	int i,j;
	int n;
	int min;
	int index1,index2;
	int depth;
	char ch;
	int sum;
	scanf("%d",&n);
	while(n>=1)
	{
	tree=(NODE*)malloc((2*n-1)*sizeof(NODE));
	for(i=0;i<n;i++)
	{
		scanf("%c%c%d",&ch,&tree[i].symbol,&tree[i].freq);
		tree[i].parent=-1;
		tree[i].tag=0;
	}
	for(i=n;i<2*n-1;i++)
	{
		min=RAND_MAX;
		for(j=0;j<i;j++)
		{
			if(tree[j].tag==0&&tree[j].freq<min)
		{
			min=tree[j].freq;
			index1=j;
			}
		}
		tree[index1].tag=1;
		min=RAND_MAX;
		for(j=0;j<i;j++)
		{
			if(tree[j].tag==0&&tree[j].freq<min)
		{
			min=tree[j].freq;
			index2=j;
			}
		}
		tree[index2].tag=1;
		tree[i].freq=tree[index1].freq+tree[index2].freq;
		tree[i].parent=-1;
		tree[i].tag=0;
		tree[index1].parent=i;
		tree[index2].parent=i;
		}
	sum=0;
	for(i=0;i<n;i++)
	{
		depth=0;
		j=i;
		while(tree[j].parent!=-1)
		{
			j=tree[j].parent;
			depth++;
		}
		sum+=depth*tree[i].freq;
	}
	printf("%d\n",sum);
	scanf("%d",&n);
	}
}

C++ :

#include <stdio.h>
#include <stdlib.h>
typedef struct node
{
	char symbol;
	int freq;
	int parent;
	int tag;
}NODE;

int main()
{
	NODE* tree;
	int i,j;
	int n;
	int min;
	int index1,index2;
	int depth;
	char ch;
	int sum;
	scanf("%d",&n);
	while(n>=1)
	{
	tree=(NODE*)malloc((2*n-1)*sizeof(NODE));
	for(i=0;i<n;i++)
	{
		scanf("%c%c%d",&ch,&tree[i].symbol,&tree[i].freq);
		tree[i].parent=-1;
		tree[i].tag=0;
	}
	for(i=n;i<2*n-1;i++)
	{
		min=RAND_MAX;
		for(j=0;j<i;j++)
		{
			if(tree[j].tag==0&&tree[j].freq<min)
		{
			min=tree[j].freq;
			index1=j;
			}
		}
		tree[index1].tag=1;
		min=RAND_MAX;
		for(j=0;j<i;j++)
		{
			if(tree[j].tag==0&&tree[j].freq<min)
		{
			min=tree[j].freq;
			index2=j;
			}
		}
		tree[index2].tag=1;
		tree[i].freq=tree[index1].freq+tree[index2].freq;
		tree[i].parent=-1;
		tree[i].tag=0;
		tree[index1].parent=i;
		tree[index2].parent=i;
		}
	sum=0;
	for(i=0;i<n;i++)
	{
		depth=0;
		j=i;
		while(tree[j].parent!=-1)
		{
			j=tree[j].parent;
			depth++;
		}
		sum+=depth*tree[i].freq;
	}
	printf("%d\n",sum);
	scanf("%d",&n);
	}
}