https://pastebin.com/Uij2gduG#include <stdio.h>
#include <stdlib.h>

int brPojavljivanja(char* s, char* c, int k){
    int i, br = 0;
    for(i = 0; *(s + i); i++)
        if(*(s + i) == *c){
            br++;
            if(br == k)
                return 1;
        }
    return 0;
}


int main(int argc, char* argv[]) {
    int i, br = 0, k;
    char c, rec[101];
    FILE* in;

    if(argc != 4) {
        printf("Manjak argumenata\n");
        return 0;
    }
    in = fopen(*(argv + 1), "r");
    if(in ==NULL) {
        printf("Neuspelo otvaranje\n");
        return 0;
    }
    k = atoi(*(argv + 3));

    while(fscanf(in, "%s", rec) != EOF){
        if(brPojavljivanja(rec, *(argv + 2), k)){
            printf("Da\n");
            return 0;}
    }
    printf("Ne\n");
    return 0;
}