Osajono

input/code.cpp: In function 'int main()':
input/code.cpp:18:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%s", buf);
                     ^

/* Osajono.cpp -- Datatahti 2016 tehtava osajono
 *
 * Eetu "Razbit" Pesonen, 2015
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <math.h>

using namespace std;

int main()
{
    // Max input string length 10^5
    char* buf = (char*)malloc(100010 * sizeof(char));
    scanf("%s", buf);
    

    unsigned int i = 0;
    while (buf[i])
    {
        buf[i] = toupper(buf[i]);
        i++;
    }

    // for counting occurences
    int* table = (int*)malloc(128 * sizeof(int));
    memset(table, 0, 128);
    
    // Even one character counts as a substr
    long long num = strlen(buf);

    // Count occurences of each char in the string
    for(i = 0; i < strlen(buf); i++)
    {
        table[(unsigned int)buf[i]] += 1;
    }

    double n, m;
    for(int i = 0; i < 128; i++)
    {
        n = table[i];
        if (n > 1)
        {
            m = n*n;
            num += (long)floor((m-n)/2);
        }
    }

    printf("%lli\n", num);

    free(buf);
    free(table);
    
    return 0;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED