Write a program to find out that how many numbers has how many duplicates ?

Question

Input : arr [10]={1,2,3,3,2,1,6,6,2,2}
output : 1 is repeated 2 times
2 is repeated 4 times
3 is repeated 2 times
6 is repeated 2 times

Answer 1

Probably easiest if you sort the array first (I used quick sort) and after that count the numbers.

void qsort(int input[], int left, int right){
if(right <= left+1){
return;
}
int t = input[right];
int w = left;
for(int i = left; i < right; i++){
if(input[i] < t){
input[w] = input[w] + input[i] - (input[i] = input[w]);
w++;
}
}
input[w] = input[w] + input[right] - (input[right] = input[w]);
qsort(input, left, w-1);
qsort(input, w+1, right);
}

void count_repeats(int input[], int n){
int t = 1;
for(int i = 1; i < n; i++){
if(input[i] == input[i-1]){
t++;
} else {
cout << input[i-1] << " is repeated " << t << " times" << endl;
t = 1;
}
}
cout << input[n-1] << " is repeated " << t << " times" << endl;
}