Joining data from two files

[tatai]

I am trying to join two files based on the DSL score. I am using the following code, but it si not working

  int DSL_1[25000], sl[25000], NCT[25000], state[25000], RU[25000];
	int DSL_2,sl_2, item, unit;
	float Quant(5);

	ifstream input_1("block_a.txt");
	ifstream input_2("block_h_bc1.txt");
	ofstream GAINS("merge_bc1.txt");

	for(int i=0; i<25000; i++)
	{
		input_1>>DSL_1[i]>>sl[i]>>NCT[i]>>state[i]>>RU[i];

	while(input_2>>DSL_2>>sl_2>>item>>unit>>Quant)
	{
		if(DSL_1[i] == DSL_2)
		{
			GAINS<<DSL_2<<'\t'<<state[i]<<'\t'<<item<<'\t'<<unit<<'\t'<<Quant<<endl;
		}
	}
	}

[Thomas1965]

What is the problem?
Does it crash?
Does it write wrong results?

How does the file data look like?

[tatai]

the output is dumping some error data, sometime it is following only one number in one column in the output file