#import <Foundation/Foundation.h>
#include <stdio.h>

NSString* input(void){
    NSData *stdinData = [[NSFileHandle fileHandleWithStandardInput] availableData];
    return [[NSString alloc] initWithData:stdinData encoding:NSUTF8StringEncoding];
}
void output(NSString *s,NSString *sep){
    NSFileHandle *fileHandle = [NSFileHandle fileHandleWithStandardOutput];
    [fileHandle writeData:[s dataUsingEncoding:NSUTF8StringEncoding]];
    [fileHandle writeData:[sep dataUsingEncoding:NSUTF8StringEncoding]];
    [fileHandle closeFile];
}

NSMutableArray* to_numarray(NSString *s){
    NSMutableArray *l = [NSMutableArray arrayWithArray:[s componentsSeparatedByString:@" "]];
    NSInteger buf = 0;
    for(int i=0;i<[l count];i++){
        buf = [[l objectAtIndex:i] integerValue];
        [l replaceObjectAtIndex:i withObject:[NSNumber numberWithInteger:buf]];
    }
    return l;
}

int main(int argc, const char * argv[]) {
    NSArray *l = [input() componentsSeparatedByString:@" "];
    NSMutableString *s = [NSMutableString stringWithString:[[l objectAtIndex:0] substringWithRange:NSMakeRange(0,1)]];
    [s appendString:[[l objectAtIndex:1] substringWithRange:NSMakeRange(0,1)]];
    [s appendString:[[l objectAtIndex:2] substringWithRange:NSMakeRange(0,1)]];
    output(s,@"\n");
    return 0;
}
