gistfile1.txt

#include <stdio.h>
#include <string.h>

int main(void){
    int a,b,R,cnt=0;
    char line1[20], line2[10];
    char *ptr;
    fgets(line1, sizeof(line1), stdin);
    ptr = strtok(line1, " ");
    a = atoi(ptr);
    while(ptr != NULL){
        ptr = strtok(NULL, " ");
        if(ptr != NULL){
            
            switch (cnt){
                case 0:
                    b = atoi(ptr);
                    break;
                case 1:
                    R = atoi(ptr);
                    break;
            }
            cnt++;
        }
    }
    printf("a: %d b: %d R: %d", a, b, R);
    return 0;
}